Wireless Resource Selection

ABSTRACT

Wireless resources may be determined for communications between wireless devices. A wireless device may select resources based on measuring one or more channels (e.g., associated with sidelink transmission, feedback transmission, etc.). Resource selection may comprise exclusion of certain resources being used for other communications and/or exclusion or selection of resources based on one or more priorities.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.63/004,716, filed on Apr. 3, 2020, and U.S. Provisional Application No.63/007,730, filed on Apr. 9, 2020. Each of the above-referencedapplications is hereby incorporated by reference in its entirety.

BACKGROUND

A base station and a wireless device communicate via uplink and/ordownlink communication.

A wireless device communicates with another device (e.g., other wirelessdevices) via sidelink communications.

SUMMARY

The following summary presents a simplified summary of certain features.The summary is not an extensive overview and is not intended to identifykey or critical elements.

Wireless devices may communicate via a communication link. A wirelessdevice may determine/select one or more wireless resources forcommunicating with another device (e.g., another wireless device).Selection of wireless resources may be based on excluding certainwireless resources that may already be in use or that may be reservedfor other wireless communications. For example, a wireless device mayexclude wireless resource(s) based on measurements associated with othercommunications (e.g., a sidelink transmission and/or a feedbacktransmission associated with the sidelink transmission) and comparingthe measurements with one or more threshold values. The one or morethreshold values may be based on one or more priorities associated witha communication. Wireless resource selection as described herein mayprovide advantages such as reduced interference, reduced powerconsumption, and/or reduced latency.

These and other features and advantages are described in greater detailbelow.

BRIEF DESCRIPTION OF THE DRAWINGS

Some features are shown by way of example, and not by limitation, in theaccompanying drawings. In the drawings, like numerals reference similarelements.

FIG. 1A and FIG. 1B show example communication networks.

FIG. 2A shows an example user plane.

FIG. 2B shows an example control plane configuration.

FIG. 3 shows example of protocol layers.

FIG. 4A shows an example downlink data flow for a user planeconfiguration.

FIG. 4B shows an example format of a Medium Access Control (MAC)subheader in a MAC Protocol Data Unit (PDU).

FIG. 5A shows an example mapping for downlink channels.

FIG. 5B shows an example mapping for uplink channels.

FIG. 6 shows example radio resource control (RRC) states and RRC statetransitions.

FIG. 7 shows an example configuration of a frame.

FIG. 8 shows an example resource configuration of one or more carriers.

FIG. 9 shows an example configuration of bandwidth parts (BWPs).

FIG. 10A shows example carrier aggregation configurations based oncomponent carriers.

FIG. 10B shows example group of cells.

FIG. 11A shows an example mapping of one or more synchronizationsignal/physical broadcast channel (SS/PBCH) blocks.

FIG. 11B shows an example mapping of one or more channel stateinformation reference signals (CSI-RSs).

FIG. 12A shows examples of downlink beam management procedures.

FIG. 12B shows examples of uplink beam management procedures.

FIG. 13A shows an example four-step random access procedure.

FIG. 13B shows an example two-step random access procedure.

FIG. 13C shows an example two-step random access procedure.

FIG. 14A shows an example of control resource set (CORESET)configurations.

FIG. 14B shows an example of a control channel element to resourceelement group (CCE-to-REG) mapping.

FIG. 15A shows an example of communications between a wireless deviceand a base station.

FIG. 15B shows example elements of a computing device that may be usedto implement any of the various devices described herein.

FIG. 16A, FIG. 16B, FIG. 16C, and FIG. 16D show examples of uplink anddownlink signal transmission.

FIG. 17 shows an example of wireless communications.

FIG. 18 shows an example of a resource pool for communication link(e.g., a sidelink).

FIG. 19 shows an example of a resource selection.

FIG. 20 shows an example of a resource indication for a transport block(TB) and a resource reservation for a TB.

FIG. 21 shows an example of a resource reservation based on sensing of awireless device.

FIG. 22 shows an example method of a resource selection procedure.

FIG. 23 shows an example of interference between communications.

FIG. 24 shows an example of interference reduction using an enhancedresource selection procedure.

FIG. 25 shows an example association mapping between a physical sidelinkshared channel (PSSCH) and a physical sidelink feedback channel (PSFCH)resource.

FIG. 26 shows an example sensing of a wireless device during a resourceselection procedure.

FIG. 27 shows an example method of PSFCH-based resource exclusion in aresource selection procedure.

FIG. 28 shows an example of interference reduction based on feedbackmeasurement in a resource selection procedure.

FIG. 29 shows an example method of PSFCH-based resource exclusion.

FIG. 30 shows an example of interference reduction based on feedbackmeasurement in a resource selection procedure.

FIG. 31 shows an example method of PSFCH-based resource exclusion in aresource selection procedure.

FIG. 32 shows an example of interference reduction based on feedbackmeasurement in a resource selection procedure.

FIG. 33 shows an example method of PSFCH-based resource exclusion basedon an offset value.

FIG. 34 shows an example method of conditional triggering of PSFCH-basedresource exclusion.

FIG. 35 shows an example method of PSFCH-based power control in aresource selection procedure.

FIG. 36 shows an example method of conditional triggering of PSFCH-basedpower control in a resource selection procedure.

FIG. 37 shows an example sensing of a wireless device during a resourceselection procedure.

FIG. 38 shows an example method of PSFCH-based resource exclusion in aresource selection procedure.

FIG. 39 shows an example method of PSFCH-based power control in aresource selection procedure.

FIG. 40 shows an example of interference reduction based on feedbackmeasurement in a resource selection procedure.

FIG. 41 is an example method of PSFCH-based resource exclusion in aresource selection procedure.

FIG. 42 is an example method of PSFCH-based power control in a resourceselection procedure.

FIG. 43A, FIG. 43B, and FIG. 43C show examples of mapping between one ormore threshold values and one or more priorities.

FIG. 44 shows an example of interference reduction based on feedbackmeasurement in a resource selection procedure.

FIG. 45 shows an example method of PSFCH-based resource exclusion in aresource selection procedure.

FIG. 46A, FIG. 46B, and FIG. 46C show examples of mapping between one ormore threshold values and one or more priorities.

FIG. 47A, FIG. 47B, and FIG. 47C show examples of mapping between one ormore offset values and one or more priorities.

DETAILED DESCRIPTION

The accompanying drawings and descriptions provide examples. It is to beunderstood that the examples shown in the drawings and/or described arenon-exclusive, and that features shown and described may be practiced inother examples. Examples are provided for operation of wirelesscommunication systems, which may be used in the technical field ofmulticarrier communication systems. More particularly, the technologydisclosed herein may relate to communications (e.g., sidelinkcommunications) between wireless devices.

FIG. 1A shows an example communication network 100. The communicationnetwork 100 may comprise a mobile communication network). Thecommunication network 100 may comprise, for example, a public landmobile network (PLMN) operated/managed/run by a network operator. Thecommunication network 100 may comprise one or more of a core network(CN) 102, a radio access network (RAN) 104, and/or a wireless device106. The communication network 100 may comprise, and/or a device withinthe communication network 100 may communicate with (e.g., via CN 102),one or more data networks (DN(s)) 108. The wireless device 106 maycommunicate with one or more DNs 108, such as public DNs (e.g., theInternet), private DNs, and/or intra-operator DNs. The wireless device106 may communicate with the one or more DNs 108 via the RAN 104 and/orvia the CN 102. The CN 102 may provide/configure the wireless device 106with one or more interfaces to the one or more DNs 108. As part of theinterface functionality, the CN 102 may set up end-to-end connectionsbetween the wireless device 106 and the one or more DNs 108,authenticate the wireless device 106, provide/configure chargingfunctionality, etc.

The wireless device 106 may communicate with the RAN 104 via radiocommunications over an air interface. The RAN 104 may communicate withthe CN 102 via various communications (e.g., wired communications and/orwireless communications). The wireless device 106 may establish aconnection with the CN 102 via the RAN 104. The RAN 104 mayprovide/configure scheduling, radio resource management, and/orretransmission protocols, for example, as part of the radiocommunications. The communication direction from the RAN 104 to thewireless device 106 over/via the air interface may be referred to as thedownlink and/or downlink communication direction. The communicationdirection from the wireless device 106 to the RAN 104 over/via the airinterface may be referred to as the uplink and/or uplink communicationdirection. Downlink transmissions may be separated and/or distinguishedfrom uplink transmissions, for example, based on at least one of:frequency division duplexing (FDD), time-division duplexing (TDD), anyother duplexing schemes, and/or one or more combinations thereof.

As used throughout, the term “wireless device” may comprise one or moreof: a mobile device, a fixed (e.g., non-mobile) device for whichwireless communication is configured or usable, a computing device, anode, a device capable of wirelessly communicating, or any other devicecapable of sending and/or receiving signals. As non-limiting examples, awireless device may comprise, for example: a telephone, a cellularphone, a Wi-Fi phone, a smartphone, a tablet, a computer, a laptop, asensor, a meter, a wearable device, an Internet of Things (IoT) device,a hotspot, a cellular repeater, a vehicle road side unit (RSU), a relaynode, an automobile, a wireless user device (e.g., user equipment (UE),a user terminal (UT), etc.), an access terminal (AT), a mobile station,a handset, a wireless transmit and receive unit (WTRU), a wirelesscommunication device, and/or any combination thereof.

The RAN 104 may comprise one or more base stations (not shown). As usedthroughout, the term “base station” may comprise one or more of: a basestation, a node, a Node B (NB), an evolved NodeB (eNB), a gNB, anng-eNB, a relay node (e.g., an integrated access and backhaul (IAB)node), a donor node (e.g., a donor eNB, a donor gNB, etc.), an accesspoint (e.g., a Wi-Fi access point), a transmission and reception point(TRP), a computing device, a device capable of wirelessly communicating,or any other device capable of sending and/or receiving signals. A basestation may comprise one or more of each element listed above. Forexample, a base station may comprise one or more TRPs. As othernon-limiting examples, a base station may comprise for example, one ormore of: a Node B (e.g., associated with Universal MobileTelecommunications System (UMTS) and/or third-generation (3G)standards), an Evolved Node B (eNB) (e.g., associated withEvolved-Universal Terrestrial Radio Access (E-UTRA) and/orfourth-generation (4G) standards), a remote radio head (RRH), a basebandprocessing unit coupled to one or more remote radio heads (RRHs), arepeater node or relay node used to extend the coverage area of a donornode, a Next Generation Evolved Node B (ng-eNB), a Generation Node B(gNB) (e.g., associated with NR and/or fifth-generation (5G) standards),an access point (AP) (e.g., associated with, for example, Wi-Fi or anyother suitable wireless communication standard), any other generationbase station, and/or any combination thereof. A base station maycomprise one or more devices, such as at least one base station centraldevice (e.g., a gNB Central Unit (gNB-CU)) and at least one base stationdistributed device (e.g., a gNB Distributed Unit (gNB-DU)).

A base station (e.g., in the RAN 104) may comprise one or more sets ofantennas for communicating with the wireless device 106 wirelessly(e.g., via an over the air interface). One or more base stations maycomprise sets (e.g., three sets or any other quantity of sets) ofantennas to respectively control multiple cells or sectors (e.g., threecells, three sectors, any other quantity of cells, or any other quantityof sectors). The size of a cell may be determined by a range at which areceiver (e.g., a base station receiver) may successfully receivetransmissions from a transmitter (e.g., a wireless device transmitter)operating in the cell. One or more cells of base stations (e.g., byalone or in combination with other cells) may provide/configure a radiocoverage to the wireless device 106 over a wide geographic area tosupport wireless device mobility. A base station comprising threesectors (e.g., or n-sector, where n refers to any quantity n) may bereferred to as a three-sector site (e.g., or an n-sector site) or athree-sector base station (e.g., an n-sector base station).

One or more base stations (e.g., in the RAN 104) may be implemented as asectored site with more or less than three sectors. One or more basestations of the RAN 104 may be implemented as an access point, as abaseband processing device/unit coupled to several RRHs, and/or as arepeater or relay node used to extend the coverage area of a node (e.g.,a donor node). A baseband processing device/unit coupled to RRHs may bepart of a centralized or cloud RAN architecture, for example, where thebaseband processing device/unit may be centralized in a pool of basebandprocessing devices/units or virtualized. A repeater node may amplify andsend (e.g., transmit, retransmit, rebroadcast, etc.) a radio signalreceived from a donor node. A relay node may perform the substantiallythe same/similar functions as a repeater node. The relay node may decodethe radio signal received from the donor node, for example, to removenoise before amplifying and sending the radio signal.

The RAN 104 may be deployed as a homogenous network of base stations(e.g., macrocell base stations) that have similar antenna patternsand/or similar high-level transmit powers. The RAN 104 may be deployedas a heterogeneous network of base stations (e.g., different basestations that have different antenna patterns). In heterogeneousnetworks, small cell base stations may be used to provide/configuresmall coverage areas, for example, coverage areas that overlap withcomparatively larger coverage areas provided/configured by other basestations (e.g., macrocell base stations). The small coverage areas maybe provided/configured in areas with high data traffic (or so-called“hotspots”) or in areas with a weak macrocell coverage. Examples ofsmall cell base stations may comprise, in order of decreasing coveragearea, microcell base stations, picocell base stations, and femtocellbase stations or home base stations.

Examples described herein may be used in a variety of types ofcommunications. For example, communications may be in accordance withthe Third-Generation Partnership Project (3GPP) (e.g., one or morenetwork elements similar to those of the communication network 100),communications in accordance with Institute of Electrical andElectronics Engineers (IEEE), communications in accordance withInternational Telecommunication Union (ITU), communications inaccordance with International Organization for Standardization (ISO),etc. The 3GPP has produced specifications for multiple generations ofmobile networks: a 3G network known as UMTS, a 4G network known asLong-Term Evolution (LTE) and LTE Advanced (LTE-A), and a 5G networkknown as 5G System (5GS) and NR system. 3GPP may produce specificationsfor additional generations of communication networks (e.g., 6G and/orany other generation of communication network). Examples may bedescribed with reference to one or more elements (e.g., the RAN) of a3GPP 5G network, referred to as a next-generation RAN (NG-RAN), or anyother communication network, such as a 3GPP network and/or a non-3GPPnetwork. Examples described herein may be applicable to othercommunication networks, such as 3G and/or 4G networks, and communicationnetworks that may not yet be finalized/specified (e.g., a 3GPP 6Gnetwork), satellite communication networks, and/or any othercommunication network. NG-RAN implements and updates 5G radio accesstechnology referred to as NR and may be provisioned to implement 4Gradio access technology and/or other radio access technologies, such asother 3GPP and/or non-3GPP radio access technologies.

FIG. 1B shows an example communication network 150. The communicationnetwork may comprise a mobile communication network. The communicationnetwork 150 may comprise, for example, a PLMN operated/managed/run by anetwork operator. The communication network 150 may comprise one or moreof: a CN 152 (e.g., a 5G core network (5G-CN)), a RAN 154 (e.g., anNG-RAN), and/or wireless devices 156A and 156B (collectively wirelessdevice(s) 156). The communication network 150 may comprise, and/or adevice within the communication network 150 may communicate with (e.g.,via CN 152), one or more data networks (DN(s)) 170. These components maybe implemented and operate in substantially the same or similar manneras corresponding components described with respect to FIG. 1A.

The CN 152 (e.g., 5G-CN) may provide/configure the wireless device(s)156 with one or more interfaces to one or more DNs 170, such as publicDNs (e.g., the Internet), private DNs, and/or intra-operator DNs. Aspart of the interface functionality, the CN 152 (e.g., 5G-CN) may set upend-to-end connections between the wireless device(s) 156 and the one ormore DNs, authenticate the wireless device(s) 156, and/orprovide/configure charging functionality. The CN 152 (e.g., the 5G-CN)may be a service-based architecture, which may differ from other CNs(e.g., such as a 3GPP 4G CN). The architecture of nodes of the CN 152(e.g., 5G-CN) may be defined as network functions that offer servicesvia interfaces to other network functions. The network functions of theCN 152 (e.g., 5G CN) may be implemented in several ways, for example, asnetwork elements on dedicated or shared hardware, as software instancesrunning on dedicated or shared hardware, and/or as virtualized functionsinstantiated on a platform (e.g., a cloud-based platform).

The CN 152 (e.g., 5G-CN) may comprise an Access and Mobility ManagementFunction (AMF) device 158A and/or a User Plane Function (UPF) device158B, which may be separate components or one component AMF/UPF device158. The UPF device 158B may serve as a gateway between a RAN 154 (e.g.,NG-RAN) and the one or more DNs 170. The UPF device 158B may performfunctions, such as: packet routing and forwarding, packet inspection anduser plane policy rule enforcement, traffic usage reporting, uplinkclassification to support routing of traffic flows to the one or moreDNs 170, quality of service (QoS) handling for the user plane (e.g.,packet filtering, gating, uplink/downlink rate enforcement, and uplinktraffic verification), downlink packet buffering, and/or downlink datanotification triggering. The UPF device 158B may serve as an anchorpoint for intra-/inter-Radio Access Technology (RAT) mobility, anexternal protocol (or packet) data unit (PDU) session point ofinterconnect to the one or more DNs, and/or a branching point to supporta multi-homed PDU session. The wireless device(s) 156 may be configuredto receive services via a PDU session, which may be a logical connectionbetween a wireless device and a DN.

The AMF device 158A may perform functions, such as: Non-Access Stratum(NAS) signaling termination, NAS signaling security, Access Stratum (AS)security control, inter-CN node signaling for mobility between accessnetworks (e.g., 3GPP access networks and/or non-3GPP networks), idlemode wireless device reachability (e.g., idle mode UE reachability forcontrol and execution of paging retransmission), registration areamanagement, intra-system and inter-system mobility support, accessauthentication, access authorization including checking of roamingrights, mobility management control (e.g., subscription and policies),network slicing support, and/or session management function (SMF)selection. NAS may refer to the functionality operating between a CN anda wireless device, and AS may refer to the functionality operatingbetween a wireless device and a RAN.

The CN 152 (e.g., 5G-CN) may comprise one or more additional networkfunctions that may not be shown in FIG. 1B. The CN 152 (e.g., 5G-CN) maycomprise one or more devices implementing at least one of: a SessionManagement Function (SMF), an NR Repository Function (NRF), a PolicyControl Function (PCF), a Network Exposure Function (NEF), a UnifiedData Management (UDM), an Application Function (AF), an AuthenticationServer Function (AUSF), and/or any other function.

The RAN 154 (e.g., NG-RAN) may communicate with the wireless device(s)156 via radio communications (e.g., an over the air interface). Thewireless device(s) 156 may communicate with the CN 152 via the RAN 154.The RAN 154 (e.g., NG-RAN) may comprise one or more first-type basestations (e.g., gNBs comprising a gNB 160A and a gNB 160B (collectivelygNBs 160)) and/or one or more second-type base stations (e.g., ng eNBscomprising an ng-eNB 162A and an ng-eNB 162B (collectively ng eNBs162)). The RAN 154 may comprise one or more of any quantity of types ofbase station. The gNBs 160 and ng eNBs 162 may be referred to as basestations. The base stations (e.g., the gNBs 160 and ng eNBs 162) maycomprise one or more sets of antennas for communicating with thewireless device(s) 156 wirelessly (e.g., an over an air interface). Oneor more base stations (e.g., the gNBs 160 and/or the ng eNBs 162) maycomprise multiple sets of antennas to respectively control multiplecells (or sectors). The cells of the base stations (e.g., the gNBs 160and the ng-eNBs 162) may provide a radio coverage to the wirelessdevice(s) 156 over a wide geographic area to support wireless devicemobility.

The base stations (e.g., the gNBs 160 and/or the ng-eNBs 162) may beconnected to the CN 152 (e.g., 5G CN) via a first interface (e.g., an NGinterface) and to other base stations via a second interface (e.g., anXn interface). The NG and Xn interfaces may be established using directphysical connections and/or indirect connections over an underlyingtransport network, such as an internet protocol (IP) transport network.The base stations (e.g., the gNBs 160 and/or the ng-eNBs 162) maycommunicate with the wireless device(s) 156 via a third interface (e.g.,a Uu interface). A base station (e.g., the gNB 160A) may communicatewith the wireless device 156A via a Uu interface. The NG, Xn, and Uuinterfaces may be associated with a protocol stack. The protocol stacksassociated with the interfaces may be used by the network elements shownin FIG. 1B to exchange data and signaling messages. The protocol stacksmay comprise two planes: a user plane and a control plane. Any otherquantity of planes may be used (e.g., in a protocol stack). The userplane may handle data of interest to a user. The control plane mayhandle signaling messages of interest to the network elements.

One or more base stations (e.g., the gNBs 160 and/or the ng-eNBs 162)may communicate with one or more AMF/UPF devices, such as the AMF/UPF158, via one or more interfaces (e.g., NG interfaces). A base station(e.g., the gNB 160A) may be in communication with, and/or connected to,the UPF 158B of the AMF/UPF 158 via an NG-User plane (NG-U) interface.The NG-U interface may provide/perform delivery (e.g., non-guaranteeddelivery) of user plane PDUs between a base station (e.g., the gNB 160A)and a UPF device (e.g., the UPF 158B). The base station (e.g., the gNB160A) may be in communication with, and/or connected to, an AMF device(e.g., the AMF 158A) via an NG-Control plane (NG-C) interface. The NG-Cinterface may provide/perform, for example, NG interface management,wireless device context management (e.g., UE context management),wireless device mobility management (e.g., UE mobility management),transport of NAS messages, paging, PDU session management, configurationtransfer, and/or warning message transmission.

A wireless device may access the base station, via an interface (e.g.,Uu interface), for the user plane configuration and the control planeconfiguration. The base stations (e.g., gNBs 160) may provide user planeand control plane protocol terminations towards the wireless device(s)156 via the Uu interface. A base station (e.g., the gNB 160A) mayprovide user plane and control plane protocol terminations toward thewireless device 156A over a Uu interface associated with a firstprotocol stack. A base station (e.g., the ng-eNBs 162) may provideEvolved UMTS Terrestrial Radio Access (E UTRA) user plane and controlplane protocol terminations towards the wireless device(s) 156 via a Uuinterface (e.g., where E UTRA may refer to the 3GPP 4G radio-accesstechnology). A base station (e.g., the ng-eNB 162B) may provide E UTRAuser plane and control plane protocol terminations towards the wirelessdevice 156B via a Uu interface associated with a second protocol stack.The user plane and control plane protocol terminations may comprise, forexample, NR user plane and control plane protocol terminations, 4G userplane and control plane protocol terminations, etc.

The CN 152 (e.g., 5G-CN) may be configured to handle one or more radioaccesses (e.g., NR, 4G, and/or any other radio accesses). It may also bepossible for an NR network/device (or any first network/device) toconnect to a 4G core network/device (or any second network/device) in anon-standalone mode (e.g., non-standalone operation). In anon-standalone mode/operation, a 4G core network may be used to provide(or at least support) control-plane functionality (e.g., initial access,mobility, and/or paging). Although only one AMF/UPF 158 is shown in FIG.1B, one or more base stations (e.g., one or more gNBs and/or one or moreng-eNBs) may be connected to multiple AMF/UPF nodes, for example, toprovide redundancy and/or to load share across the multiple AMF/UPFnodes.

An interface (e.g., Uu, Xn, and/or NG interfaces) between networkelements (e.g., the network elements shown in FIG. 1B) may be associatedwith a protocol stack that the network elements may use to exchange dataand signaling messages. A protocol stack may comprise two planes: a userplane and a control plane. Any other quantity of planes may be used(e.g., in a protocol stack). The user plane may handle data associatedwith a user (e.g., data of interest to a user). The control plane mayhandle data associated with one or more network elements (e.g.,signaling messages of interest to the network elements).

The communication network 100 in FIG. 1A and/or the communicationnetwork 150 in FIG. 1B may comprise any quantity/number and/or type ofdevices, such as, for example, computing devices, wireless devices,mobile devices, handsets, tablets, laptops, internet of things (IoT)devices, hotspots, cellular repeaters, computing devices, and/or, moregenerally, user equipment (e.g., UE). Although one or more of the abovetypes of devices may be referenced herein (e.g., UE, wireless device,computing device, etc.), it should be understood that any device hereinmay comprise any one or more of the above types of devices or similardevices. The communication network, and any other network referencedherein, may comprise an LTE network, a 5G network, a satellite network,and/or any other network for wireless communications (e.g., any 3GPPnetwork and/or any non-3GPP network). Apparatuses, systems, and/ormethods described herein may generally be described as implemented onone or more devices (e.g., wireless device, base station, eNB, gNB,computing device, etc.), in one or more networks, but it will beunderstood that one or more features and steps may be implemented on anydevice and/or in any network.

FIG. 2A shows an example user plane configuration. The user planeconfiguration may comprise, for example, an NR user plane protocolstack. FIG. 2B shows an example control plane configuration. The controlplane configuration may comprise, for example, an NR control planeprotocol stack. One or more of the user plane configuration and/or thecontrol plane configuration may use a Uu interface that may be between awireless device 210 and a base station 220. The protocol stacks shown inFIG. 2A and FIG. 2B may be substantially the same or similar to thoseused for the Uu interface between, for example, the wireless device 156Aand the base station 160A shown in FIG. 1B.

A user plane configuration (e.g., an NR user plane protocol stack) maycomprise multiple layers (e.g., five layers or any other quantity oflayers) implemented in the wireless device 210 and the base station 220(e.g., as shown in FIG. 2A). At the bottom of the protocol stack,physical layers (PHYs) 211 and 221 may provide transport services to thehigher layers of the protocol stack and may correspond to layer 1 of theOpen Systems Interconnection (OSI) model. The protocol layers above PHY211 may comprise a medium access control layer (MAC) 212, a radio linkcontrol layer (RLC) 213, a packet data convergence protocol layer (PDCP)214, and/or a service data application protocol layer (SDAP) 215. Theprotocol layers above PHY 221 may comprise a medium access control layer(MAC) 222, a radio link control layer (RLC) 223, a packet dataconvergence protocol layer (PDCP) 224, and/or a service data applicationprotocol layer (SDAP) 225. One or more of the four protocol layers abovePHY 211 may correspond to layer 2, or the data link layer, of the OSImodel. One or more of the four protocol layers above PHY 221 maycorrespond to layer 2, or the data link layer, of the OSI model.

FIG. 3 shows an example of protocol layers. The protocol layers maycomprise, for example, protocol layers of the NR user plane protocolstack. One or more services may be provided between protocol layers.SDAPs (e.g., SDAPS 215 and 225 shown in FIG. 2A and FIG. 3) may performQuality of Service (QoS) flow handling. A wireless device (e.g., thewireless devices 106, 156A, 156B, and 210) may receive servicesthrough/via a PDU session, which may be a logical connection between thewireless device and a DN. The PDU session may have one or more QoS flows310. A UPF (e.g., the UPF 158B) of a CN may map IP packets to the one ormore QoS flows of the PDU session, for example, based on one or more QoSrequirements (e.g., in terms of delay, data rate, error rate, and/or anyother quality/service requirement). The SDAPs 215 and 225 may performmapping/de-mapping between the one or more QoS flows 310 and one or moreradio bearers 320 (e.g., data radio bearers). The mapping/de-mappingbetween the one or more QoS flows 310 and the radio bearers 320 may bedetermined by the SDAP 225 of the base station 220. The SDAP 215 of thewireless device 210 may be informed of the mapping between the QoS flows310 and the radio bearers 320 via reflective mapping and/or controlsignaling received from the base station 220. For reflective mapping,the SDAP 225 of the base station 220 may mark the downlink packets witha QoS flow indicator (QFI), which may bemonitored/detected/identified/indicated/observed by the SDAP 215 of thewireless device 210 to determine the mapping/de-mapping between the oneor more QoS flows 310 and the radio bearers 320.

PDCPs (e.g., the PDCPs 214 and 224 shown in FIG. 2A and FIG. 3) mayperform header compression/decompression, for example, to reduce theamount of data that may need to be transmitted over the air interface,ciphering/deciphering to prevent unauthorized decoding of datatransmitted over the air interface, and/or integrity protection (e.g.,to ensure control messages originate from intended sources). The PDCPs214 and 224 may perform retransmissions of undelivered packets,in-sequence delivery and reordering of packets, and/or removal ofpackets received in duplicate due to, for example, a handover (e.g., anintra-gNB handover). The PDCPs 214 and 224 may perform packetduplication, for example, to improve the likelihood of the packet beingreceived. A receiver may receive the packet in duplicate and may removeany duplicate packets. Packet duplication may be useful for certainservices, such as services that require high reliability.

The PDCP layers (e.g., PDCPs 214 and 224) may perform mapping/de-mappingbetween a split radio bearer and RLC channels (e.g., RLC channels 330)(e.g., in a dual connectivity example/configuration). Dual connectivitymay refer to a technique that allows a wireless device to communicatewith multiple cells (e.g., two cells) or, more generally, multiple cellgroups comprising: a master cell group (MCG) and a secondary cell group(SCG). A split bearer may be configured and/or used, for example, if asingle radio bearer (e.g., such as one of the radio bearersprovided/configured by the PDCPs 214 and 224 as a service to the SDAPs215 and 225) is handled by cell groups in dual connectivity. The PDCPs214 and 224 may map/de-map between the split radio bearer and RLCchannels 330 belonging to the cell groups.

RLC layers (e.g., RLCs 213 and 223) may perform segmentation,retransmission via Automatic Repeat Request (ARQ), and/or removal ofduplicate data units received from MAC layers (e.g., MACs 212 and 222,respectively). The RLC layers (e.g., RLCs 213 and 223) may supportmultiple transmission modes (e.g., three transmission modes: transparentmode (TM); unacknowledged mode (UM); and acknowledged mode (AM)). TheRLC layers may perform one or more of the noted functions, for example,based on the transmission mode an RLC layer is operating. The RLCconfiguration may be per logical channel The RLC configuration may notdepend on numerologies and/or Transmission Time Interval (TTI) durations(or other durations). The RLC layers (e.g., RLCs 213 and 223) mayprovide/configure RLC channels as a service to the PDCP layers (e.g.,PDCPs 214 and 224, respectively), such as shown in FIG. 3.

The MAC layers (e.g., MACs 212 and 222) may performmultiplexing/demultiplexing of logical channels and/or mapping betweenlogical channels and transport channels. The multiplexing/demultiplexingmay comprise multiplexing/demultiplexing of data units/data portions,belonging to the one or more logical channels, into/from TransportBlocks (TBs) delivered to/from the PHY layers (e.g., PHYs 211 and 221,respectively). The MAC layer of a base station (e.g., MAC 222) may beconfigured to perform scheduling, scheduling information reporting,and/or priority handling between wireless devices via dynamicscheduling. Scheduling may be performed by a base station (e.g., thebase station 220 at the MAC 222) for downlink/or and uplink. The MAClayers (e.g., MACs 212 and 222) may be configured to perform errorcorrection(s) via Hybrid Automatic Repeat Request (HARQ) (e.g., one HARQentity per carrier in case of Carrier Aggregation (CA)), priorityhandling between logical channels of the wireless device 210 via logicalchannel prioritization and/or padding. The MAC layers (e.g., MACs 212and 222) may support one or more numerologies and/or transmissiontimings. Mapping restrictions in a logical channel prioritization maycontrol which numerology and/or transmission timing a logical channelmay use. The MAC layers (e.g., the MACs 212 and 222) mayprovide/configure logical channels 340 as a service to the RLC layers(e.g., the RLCs 213 and 223).

The PHY layers (e.g., PHYs 211 and 221) may perform mapping of transportchannels to physical channels and/or digital and analog signalprocessing functions, for example, for sending and/or receivinginformation (e.g., via an over the air interface). The digital and/oranalog signal processing functions may comprise, for example,coding/decoding and/or modulation/demodulation. The PHY layers (e.g.,PHYs 211 and 221) may perform multi-antenna mapping. The PHY layers(e.g., the PHYs 211 and 221) may provide/configure one or more transportchannels (e.g., transport channels 350) as a service to the MAC layers(e.g., the MACs 212 and 222, respectively).

FIG. 4A shows an example downlink data flow for a user planeconfiguration. The user plane configuration may comprise, for example,the NR user plane protocol stack shown in FIG. 2A. One or more TBs maybe generated, for example, based on a data flow via a user planeprotocol stack. As shown in FIG. 4A, a downlink data flow of three IPpackets (n, n+1, and m) via the NR user plane protocol stack maygenerate two TBs (e.g., at the base station 220). An uplink data flowvia the NR user plane protocol stack may be similar to the downlink dataflow shown in FIG. 4A. The three IP packets (n, n+1, and m) may bedetermined from the two TBs, for example, based on the uplink data flowvia an NR user plane protocol stack. A first quantity of packets (e.g.,three or any other quantity) may be determined from a second quantity ofTBs (e.g., two or another quantity).

The downlink data flow may begin, for example, if the SDAP 225 receivesthe three IP packets (or other quantity of IP packets) from one or moreQoS flows and maps the three packets (or other quantity of packets) toradio bearers (e.g., radio bearers 402 and 404). The SDAP 225 may mapthe IP packets n and n+1 to a first radio bearer 402 and map the IPpacket m to a second radio bearer 404. An SDAP header (labeled with “H”preceding each SDAP SDU shown in FIG. 4A) may be added to an IP packetto generate an SDAP PDU, which may be referred to as a PDCP SDU. Thedata unit transferred from/to a higher protocol layer may be referred toas a service data unit (SDU) of the lower protocol layer, and the dataunit transferred to/from a lower protocol layer may be referred to as aprotocol data unit (PDU) of the higher protocol layer. As shown in FIG.4A, the data unit from the SDAP 225 may be an SDU of lower protocollayer PDCP 224 (e.g., PDCP SDU) and may be a PDU of the SDAP 225 (e.g.,SDAP PDU).

Each protocol layer (e.g., protocol layers shown in FIG. 4A) or at leastsome protocol layers may: perform its own function(s) (e.g., one or morefunctions of each protocol layer described with respect to FIG. 3), adda corresponding header, and/or forward a respective output to the nextlower layer (e.g., its respective lower layer). The PDCP 224 may performan IP-header compression and/or ciphering. The PDCP 224 may forward itsoutput (e.g., a PDCP PDU, which is an RLC SDU) to the RLC 223. The RLC223 may optionally perform segmentation (e.g., as shown for IP packet min FIG. 4A). The RLC 223 may forward its outputs (e.g., two RLC PDUs,which are two MAC SDUs, generated by adding respective subheaders to twoSDU segments (SDU Segs)) to the MAC 222. The MAC 222 may multiplex anumber of RLC PDUs (MAC SDUs). The MAC 222 may attach a MAC subheader toan RLC PDU (MAC SDU) to form a TB. The MAC subheaders may be distributedacross the MAC PDU (e.g., in an NR configuration as shown in FIG. 4A).The MAC subheaders may be entirely located at the beginning of a MAC PDU(e.g., in an LTE configuration). The NR MAC PDU structure may reduce aprocessing time and/or associated latency, for example, if the MAC PDUsubheaders are computed before assembling the full MAC PDU.

FIG. 4B shows an example format of a MAC subheader in a MAC PDU. A MACPDU may comprise a MAC subheader (H) and a MAC SDU. Each of one or moreMAC subheaders may comprise an SDU length field for indicating thelength (e.g., in bytes) of the MAC SDU to which the MAC subheadercorresponds; a logical channel identifier (LCID) field foridentifying/indicating the logical channel from which the MAC SDUoriginated to aid in the demultiplexing process; a flag (F) forindicating the size of the SDU length field; and a reserved bit (R)field for future use.

One or more MAC control elements (CEs) may be added to, or insertedinto, the MAC PDU by a MAC layer, such as MAC 223 or MAC 222. As shownin FIG. 4B, two MAC CEs may be inserted/added before two MAC PDUs. TheMAC CEs may be inserted/added at the beginning of a MAC PDU for downlinktransmissions (as shown in FIG. 4B). One or more MAC CEs may beinserted/added at the end of a MAC PDU for uplink transmissions. MAC CEsmay be used for in band control signaling. Example MAC CEs may comprisescheduling-related MAC CEs, such as buffer status reports and powerheadroom reports; activation/deactivation MAC CEs (e.g., MAC CEs foractivation/deactivation of PDCP duplication detection, channel stateinformation (CSI) reporting, sounding reference signal (SRS)transmission, and prior configured components); discontinuous reception(DRX)-related MAC CEs; timing advance MAC CEs; and random access-relatedMAC CEs. A MAC CE may be preceded by a MAC subheader with a similarformat as described for the MAC subheader for MAC SDUs and may beidentified with a reserved value in the LCID field that indicates thetype of control information included in the corresponding MAC CE.

FIG. 5A shows an example mapping for downlink channels. The mapping foruplink channels may comprise mapping between channels (e.g., logicalchannels, transport channels, and physical channels) for downlink. FIG.5B shows an example mapping for uplink channels. The mapping for uplinkchannels may comprise mapping between channels (e.g., logical channels,transport channels, and physical channels) for uplink. Information maybe passed through/via channels between the RLC, the MAC, and the PHYlayers of a protocol stack (e.g., the NR protocol stack). A logicalchannel may be used between the RLC and the MAC layers. The logicalchannel may be classified/indicated as a control channel that may carrycontrol and/or configuration information (e.g., in the NR controlplane), or as a traffic channel that may carry data (e.g., in the NRuser plane). A logical channel may be classified/indicated as adedicated logical channel that may be dedicated to a specific wirelessdevice, and/or as a common logical channel that may be used by more thanone wireless device (e.g., a group of wireless device).

A logical channel may be defined by the type of information it carries.The set of logical channels (e.g., in an NR configuration) may compriseone or more channels described below. A paging control channel (PCCH)may comprise/carry one or more paging messages used to page a wirelessdevice whose location is not known to the network on a cell level. Abroadcast control channel (BCCH) may comprise/carry system informationmessages in the form of a master information block (MIB) and severalsystem information blocks (SIBs). The system information messages may beused by wireless devices to obtain information about how a cell isconfigured and how to operate within the cell. A common control channel(CCCH) may comprise/carry control messages together with random access.A dedicated control channel (DCCH) may comprise/carry control messagesto/from a specific wireless device to configure the wireless device withconfiguration information. A dedicated traffic channel (DTCH) maycomprise/carry user data to/from a specific wireless device.

Transport channels may be used between the MAC and PHY layers. Transportchannels may be defined by how the information they carry issent/transmitted (e.g., via an over the air interface). The set oftransport channels (e.g., that may be defined by an NR configuration orany other configuration) may comprise one or more of the followingchannels. A paging channel (PCH) may comprise/carry paging messages thatoriginated from the PCCH. A broadcast channel (BCH) may comprise/carrythe MIB from the BCCH. A downlink shared channel (DL-SCH) maycomprise/carry downlink data and signaling messages, including the SIBsfrom the BCCH. An uplink shared channel (UL-SCH) may comprise/carryuplink data and signaling messages. A random access channel (RACH) mayprovide a wireless device with an access to the network without anyprior scheduling.

The PHY layer may use physical channels to pass/transfer informationbetween processing levels of the PHY layer. A physical channel may havean associated set of time-frequency resources for carrying theinformation of one or more transport channels. The PHY layer maygenerate control information to support the low-level operation of thePHY layer. The PHY layer may provide/transfer the control information tothe lower levels of the PHY layer via physical control channels (e.g.,referred to as L1/L2 control channels). The set of physical channels andphysical control channels (e.g., that may be defined by an NRconfiguration or any other configuration) may comprise one or more ofthe following channels. A physical broadcast channel (PBCH) maycomprise/carry the MIB from the BCH. A physical downlink shared channel(PDSCH) may comprise/carry downlink data and signaling messages from theDL-SCH, as well as paging messages from the PCH. A physical downlinkcontrol channel (PDCCH) may comprise/carry downlink control information(DCI), which may comprise downlink scheduling commands, uplinkscheduling grants, and uplink power control commands A physical uplinkshared channel (PUSCH) may comprise/carry uplink data and signalingmessages from the UL-SCH and in some instances uplink controlinformation (UCI) as described below. A physical uplink control channel(PUCCH) may comprise/carry UCI, which may comprise HARQ acknowledgments,channel quality indicators (CQI), pre-coding matrix indicators (PMI),rank indicators (RI), and scheduling requests (SR). A physical randomaccess channel (PRACH) may be used for random access.

The physical layer may generate physical signals to support thelow-level operation of the physical layer, which may be similar to thephysical control channels. As shown in FIG. 5A and FIG. 5B, the physicallayer signals (e.g., that may be defined by an NR configuration or anyother configuration) may comprise primary synchronization signals (PSS),secondary synchronization signals (SSS), channel state informationreference signals (CSI-RS), demodulation reference signals (DM-RS),sounding reference signals (SRS), phase-tracking reference signals (PTRS), and/or any other signals.

One or more of the channels (e.g., logical channels, transport channels,physical channels, etc.) may be used to carry out functions associatedwith the control plan protocol stack (e.g., NR control plane protocolstack). FIG. 2B shows an example control plane configuration (e.g., anNR control plane protocol stack). As shown in FIG. 2B, the control planeconfiguration (e.g., the NR control plane protocol stack) may usesubstantially the same/similar one or more protocol layers (e.g., PHY211 and 221, MAC 212 and 222, RLC 213 and 223, and PDCP 214 and 224) asthe example user plane configuration (e.g., the NR user plane protocolstack). Similar four protocol layers may comprise the PHYs 211 and 221,the MACs 212 and 222, the RLCs 213 and 223, and the PDCPs 214 and 224.The control plane configuration (e.g., the NR control plane stack) mayhave radio resource controls (RRCs) 216 and 226 and NAS protocols 217and 237 at the top of the control plane configuration (e.g., the NRcontrol plane protocol stack), for example, instead of having the SDAPs215 and 225. The control plane configuration may comprise an AMF 230comprising the NAS protocol 237.

The NAS protocols 217 and 237 may provide control plane functionalitybetween the wireless device 210 and the AMF 230 (e.g., the AMF 158A orany other AMF) and/or, more generally, between the wireless device 210and a CN (e.g., the CN 152 or any other CN). The NAS protocols 217 and237 may provide control plane functionality between the wireless device210 and the AMF 230 via signaling messages, referred to as NAS messages.There may be no direct path between the wireless device 210 and the AMF230 via which the NAS messages may be transported. The NAS messages maybe transported using the AS of the Uu and NG interfaces. The NASprotocols 217 and 237 may provide control plane functionality, such asauthentication, security, a connection setup, mobility management,session management, and/or any other functionality.

The RRCs 216 and 226 may provide/configure control plane functionalitybetween the wireless device 210 and the base station 220 and/or, moregenerally, between the wireless device 210 and the RAN (e.g., the basestation 220). The RRC layers 216 and 226 may provide/configure controlplane functionality between the wireless device 210 and the base station220 via signaling messages, which may be referred to as RRC messages.The RRC messages may be transmitted between the wireless device 210 andthe RAN (e.g., the base station 220) using signaling radio bearers andthe same/similar PDCP, RLC, MAC, and PHY protocol layers. The MAC layermay multiplex control-plane and user-plane data into the same TB. TheRRC layers 216 and 226 may provide/configure control planefunctionality, such as one or more of the following functionalities:broadcast of system information related to AS and NAS; paging initiatedby the CN or the RAN; establishment, maintenance and release of an RRCconnection between the wireless device 210 and the RAN (e.g., the basestation 220); security functions including key management;establishment, configuration, maintenance and release of signaling radiobearers and data radio bearers; mobility functions; QoS managementfunctions; wireless device measurement reporting (e.g., the wirelessdevice measurement reporting) and control of the reporting; detection ofand recovery from radio link failure (RLF); and/or NAS message transfer.As part of establishing an RRC connection, RRC layers 216 and 226 mayestablish an RRC context, which may involve configuring parameters forcommunication between the wireless device 210 and the RAN (e.g., thebase station 220).

FIG. 6 shows example RRC states and RRC state transitions. An RRC stateof a wireless device may be changed to another RRC state (e.g., RRCstate transitions of a wireless device). The wireless device may besubstantially the same or similar to the wireless device 106, 210, orany other wireless device. A wireless device may be in at least one of aplurality of states, such as three RRC states comprising RRC connected602 (e.g., RRC_CONNECTED), RRC idle 606 (e.g., RRC_IDLE), and RRCinactive 604 (e.g., RRC_INACTIVE). The RRC inactive 604 may be RRCconnected but inactive.

An RRC connection may be established for the wireless device. Forexample, this may be during an RRC connected state. During the RRCconnected state (e.g., during the RRC connected 602), the wirelessdevice may have an established RRC context and may have at least one RRCconnection with a base station. The base station may be similar to oneof the one or more base stations (e.g., one or more base stations of theRAN 104 shown in FIG. 1A, one of the gNBs 160 or ng-eNBs 162 shown inFIG. 1B, the base station 220 shown in FIG. 2A and FIG. 2B, or any otherbase stations). The base station with which the wireless device isconnected (e.g., has established an RRC connection) may have the RRCcontext for the wireless device. The RRC context, which may be referredto as a wireless device context (e.g., the UE context), may compriseparameters for communication between the wireless device and the basestation. These parameters may comprise, for example, one or more of: AScontexts; radio link configuration parameters; bearer configurationinformation (e.g., relating to a data radio bearer, a signaling radiobearer, a logical channel, a QoS flow, and/or a PDU session); securityinformation; and/or layer configuration information (e.g., PHY, MAC,RLC, PDCP, and/or SDAP layer configuration information). During the RRCconnected state (e.g., the RRC connected 602), mobility of the wirelessdevice may be managed/controlled by an RAN (e.g., the RAN 104 or the NGRAN 154). The wireless device may measure received signal levels (e.g.,reference signal levels, reference signal received power, referencesignal received quality, received signal strength indicator, etc.) basedon one or more signals sent from a serving cell and neighboring cells.The wireless device may report these measurements to a serving basestation (e.g., the base station currently serving the wireless device).The serving base station of the wireless device may request a handoverto a cell of one of the neighboring base stations, for example, based onthe reported measurements. The RRC state may transition from the RRCconnected state (e.g., RRC connected 602) to an RRC idle state (e.g.,the RRC idle 606) via a connection release procedure 608. The RRC statemay transition from the RRC connected state (e.g., RRC connected 602) tothe RRC inactive state (e.g., RRC inactive 604) via a connectioninactivation procedure 610.

An RRC context may not be established for the wireless device. Forexample, this may be during the RRC idle state. During the RRC idlestate (e.g., the RRC idle 606), an RRC context may not be establishedfor the wireless device. During the RRC idle state (e.g., the RRC idle606), the wireless device may not have an RRC connection with the basestation. During the RRC idle state (e.g., the RRC idle 606), thewireless device may be in a sleep state for the majority of the time(e.g., to conserve battery power). The wireless device may wake upperiodically (e.g., once in every discontinuous reception (DRX) cycle)to monitor for paging messages (e.g., paging messages set from the RAN).Mobility of the wireless device may be managed by the wireless devicevia a procedure of a cell reselection. The RRC state may transition fromthe RRC idle state (e.g., the RRC idle 606) to the RRC connected state(e.g., the RRC connected 602) via a connection establishment procedure612, which may involve a random access procedure.

A previously established RRC context may be maintained for the wirelessdevice. For example, this may be during the RRC inactive state. Duringthe RRC inactive state (e.g., the RRC inactive 604), the RRC contextpreviously established may be maintained in the wireless device and thebase station. The maintenance of the RRC context may enable/allow a fasttransition to the RRC connected state (e.g., the RRC connected 602) withreduced signaling overhead as compared to the transition from the RRCidle state (e.g., the RRC idle 606) to the RRC connected state (e.g.,the RRC connected 602). During the RRC inactive state (e.g., the RRCinactive 604), the wireless device may be in a sleep state and mobilityof the wireless device may be managed/controlled by the wireless devicevia a cell reselection. The RRC state may transition from the RRCinactive state (e.g., the RRC inactive 604) to the RRC connected state(e.g., the RRC connected 602) via a connection resume procedure 614. TheRRC state may transition from the RRC inactive state (e.g., the RRCinactive 604) to the RRC idle state (e.g., the RRC idle 606) via aconnection release procedure 616 that may be the same as or similar toconnection release procedure 608.

An RRC state may be associated with a mobility management mechanism.During the RRC idle state (e.g., RRC idle 606) and the RRC inactivestate (e.g., the RRC inactive 604), mobility may be managed/controlledby the wireless device via a cell reselection. The purpose of mobilitymanagement during the RRC idle state (e.g., the RRC idle 606) or duringthe RRC inactive state (e.g., the RRC inactive 604) may be toenable/allow the network to be able to notify the wireless device of anevent via a paging message without having to broadcast the pagingmessage over the entire mobile communications network. The mobilitymanagement mechanism used during the RRC idle state (e.g., the RRC idle606) or during the RRC idle state (e.g., the RRC inactive 604) mayenable/allow the network to track the wireless device on a cell-grouplevel, for example, so that the paging message may be broadcast over thecells of the cell group that the wireless device currently resideswithin (e.g. instead of sending the paging message over the entiremobile communication network). The mobility management mechanisms forthe RRC idle state (e.g., the RRC idle 606) and the RRC inactive state(e.g., the RRC inactive 604) may track the wireless device on acell-group level. The mobility management mechanisms may do thetracking, for example, using different granularities of grouping. Theremay be a plurality of levels of cell-grouping granularity (e.g., threelevels of cell-grouping granularity: individual cells; cells within aRAN area identified by a RAN area identifier (RAI); and cells within agroup of RAN areas, referred to as a tracking area and identified by atracking area identifier (TAI)).

Tracking areas may be used to track the wireless device (e.g., trackingthe location of the wireless device at the CN level). The CN (e.g., theCN 102, the 5G CN 152, or any other CN) may send to the wireless devicea list of TAIs associated with a wireless device registration area(e.g., a UE registration area). A wireless device may perform aregistration update with the CN to allow the CN to update the locationof the wireless device and provide the wireless device with a new the UEregistration area, for example, if the wireless device moves (e.g., viaa cell reselection) to a cell associated with a TAI that may not beincluded in the list of TAIs associated with the UE registration area.

RAN areas may be used to track the wireless device (e.g., the locationof the wireless device at the RAN level). For a wireless device in anRRC inactive state (e.g., the RRC inactive 604), the wireless device maybe assigned/provided/configured with a RAN notification area. A RANnotification area may comprise one or more cell identities (e.g., a listof RAIs and/or a list of TAIs). A base station may belong to one or moreRAN notification areas. A cell may belong to one or more RANnotification areas. A wireless device may perform a notification areaupdate with the RAN to update the RAN notification area of the wirelessdevice, for example, if the wireless device moves (e.g., via a cellreselection) to a cell not included in the RAN notification areaassigned/provided/configured to the wireless device.

A base station storing an RRC context for a wireless device or a lastserving base station of the wireless device may be referred to as ananchor base station. An anchor base station may maintain an RRC contextfor the wireless device at least during a period of time that thewireless device stays in a RAN notification area of the anchor basestation and/or during a period of time that the wireless device stays inan RRC inactive state (e.g., RRC inactive 604).

A base station (e.g., gNBs 160 in FIG. 1B or any other base station) maybe split in two parts: a central unit (e.g., a base station centralunit, such as a gNB CU) and one or more distributed units (e.g., a basestation distributed unit, such as a gNB DU). A base station central unit(CU) may be coupled to one or more base station distributed units (DUs)using an Fl interface (e.g., an Fl interface defined in an NRconfiguration). The base station CU may comprise the RRC, the PDCP, andthe SDAP layers. A base station distributed unit (DU) may comprise theRLC, the MAC, and the PHY layers.

The physical signals and physical channels (e.g., described with respectto FIG. 5A and FIG. 5B) may be mapped onto one or more symbols (e.g.,orthogonal frequency divisional multiplexing (OFDM) symbols in an NRconfiguration or any other symbols). OFDM is a multicarriercommunication scheme that transmits data over F orthogonal subcarriers(or tones). The data may be mapped to a series of complex symbols (e.g.,M-quadrature amplitude modulation (M-QAM) symbols or M-phase shiftkeying (M PSK) symbols or any other modulated symbols), referred to assource symbols, and divided into F parallel symbol streams, for example,before transmission of the data. The F parallel symbol streams may betreated as if they are in the frequency domain. The F parallel symbolsmay be used as inputs to an Inverse Fast Fourier Transform (IFFT) blockthat transforms them into the time domain. The IFFT block may take in Fsource symbols at a time, one from each of the F parallel symbolstreams. The IFFT block may use each source symbol to modulate theamplitude and phase of one of F sinusoidal basis functions thatcorrespond to the F orthogonal subcarriers. The output of the IFFT blockmay be F time-domain samples that represent the summation of the Forthogonal subcarriers. The F time-domain samples may form a single OFDMsymbol. An OFDM symbol provided/output by the IFFT block may besent/transmitted over the air interface on a carrier frequency, forexample, after one or more processes (e.g., addition of a cyclic prefix)and up-conversion. The F parallel symbol streams may be mixed, forexample, using a Fast Fourier Transform (FFT) block before beingprocessed by the IFFT block. This operation may produce Discrete FourierTransform (DFT)-precoded OFDM symbols and may be used by one or morewireless devices in the uplink to reduce the peak to average power ratio(PAPR). Inverse processing may be performed on the OFDM symbol at areceiver using an FFT block to recover the data mapped to the sourcesymbols.

FIG. 7 shows an example configuration of a frame. The frame maycomprise, for example, an NR radio frame into which OFDM symbols may begrouped. A frame (e.g., an NR radio frame) may be identified/indicatedby a system frame number (SFN) or any other value. The SFN may repeatwith a period of 1024 frames. One NR frame may be 10 milliseconds (ms)in duration and may comprise 10 subframes that are 1 ms in duration. Asubframe may be divided into one or more slots (e.g., depending onnumerologies and/or different subcarrier spacings). Each of the one ormore slots may comprise, for example, 14 OFDM symbols per slot. Anyquantity of symbols, slots, or duration may be used for any timeinterval.

The duration of a slot may depend on the numerology used for the OFDMsymbols of the slot. A flexible numerology may be supported, forexample, to accommodate different deployments (e.g., cells with carrierfrequencies below 1 GHz up to cells with carrier frequencies in themm-wave range). A flexible numerology may be supported, for example, inan NR configuration or any other radio configurations. A numerology maybe defined in terms of subcarrier spacing and/or cyclic prefix duration.Subcarrier spacings may be scaled up by powers of two from a baselinesubcarrier spacing of 15 kHz. Cyclic prefix durations may be scaled downby powers of two from a baseline cyclic prefix duration of 4.7 μs, forexample, for a numerology in an NR configuration or any other radioconfigurations. Numerologies may be defined with the followingsubcarrier spacing/cyclic prefix duration combinations: 15 kHz/4.7 μs;30 kHz/2.3 μs; 60 kHz/1.2 μs; 120 kHz/0.59 μs; 240 kHz/0.29 μs, and/orany other subcarrier spacing/cyclic prefix duration combinations.

A slot may have a fixed number/quantity of OFDM symbols (e.g., 14 OFDMsymbols). A numerology with a higher subcarrier spacing may have ashorter slot duration and more slots per subframe. Examples ofnumerology-dependent slot duration and slots-per-subframe transmissionstructure are shown in FIG. 7 (the numerology with a subcarrier spacingof 240 kHz is not shown in FIG. 7). A subframe (e.g., in an NRconfiguration) may be used as a numerology-independent time reference. Aslot may be used as the unit upon which uplink and downlinktransmissions are scheduled. Scheduling (e.g., in an NR configuration)may be decoupled from the slot duration. Scheduling may start at anyOFDM symbol. Scheduling may last for as many symbols as needed for atransmission, for example, to support low latency. These partial slottransmissions may be referred to as mini-slot or sub-slot transmissions.

FIG. 8 shows an example resource configuration of one or more carriers.The resource configuration of may comprise a slot in the time andfrequency domain for an NR carrier or any other carrier. The slot maycomprise resource elements (REs) and resource blocks (RBs). A resourceelement (RE) may be the smallest physical resource (e.g., in an NRconfiguration). An RE may span one OFDM symbol in the time domain by onesubcarrier in the frequency domain, such as shown in FIG. 8. An RB mayspan twelve consecutive REs in the frequency domain, such as shown inFIG. 8. A carrier (e.g., an NR carrier) may be limited to a width of acertain quantity of RBs and/or subcarriers (e.g., 275 RBs or 275×12=3300subcarriers). Such limitation(s), if used, may limit the carrier (e.g.,NR carrier) frequency based on subcarrier spacing (e.g., carrierfrequency of 50, 100, 200, and 400 MHz for subcarrier spacings of 15,30, 60, and 120 kHz, respectively). A 400 MHz bandwidth may be set basedon a 400 MHz per carrier bandwidth limit. Any other bandwidth may be setbased on a per carrier bandwidth limit.

A single numerology may be used across the entire bandwidth of a carrier(e.g., an NR such as shown in FIG. 8). In other example configurations,multiple numerologies may be supported on the same carrier. NR and/orother access technologies may support wide carrier bandwidths (e.g., upto 400 MHz for a subcarrier spacing of 120 kHz). Not all wirelessdevices may be able to receive the full carrier bandwidth (e.g., due tohardware limitations and/or different wireless device capabilities).Receiving and/or utilizing the full carrier bandwidth may beprohibitive, for example, in terms of wireless device power consumption.A wireless device may adapt the size of the receive bandwidth of thewireless device, for example, based on the amount of traffic thewireless device is scheduled to receive (e.g., to reduce powerconsumption and/or for other purposes). Such an adaptation may bereferred to as bandwidth adaptation.

Configuration of one or more bandwidth parts (BWPs) may support one ormore wireless devices not capable of receiving the full carrierbandwidth. BWPs may support bandwidth adaptation, for example, for suchwireless devices not capable of receiving the full carrier bandwidth. ABWP (e.g., a BWP of an NR configuration) may be defined by a subset ofcontiguous RBs on a carrier. A wireless device may be configured (e.g.,via an RRC layer) with one or more downlink BWPs per serving cell andone or more uplink BWPs per serving cell (e.g., up to four downlink BWPsper serving cell and up to four uplink BWPs per serving cell). One ormore of the configured BWPs for a serving cell may be active, forexample, at a given time. The one or more BWPs may be referred to asactive BWPs of the serving cell. A serving cell may have one or morefirst active BWPs in the uplink carrier and one or more second activeBWPs in the secondary uplink carrier, for example, if the serving cellis configured with a secondary uplink carrier.

A downlink BWP from a set of configured downlink BWPs may be linked withan uplink BWP from a set of configured uplink BWPs (e.g., for unpairedspectra). A downlink BWP and an uplink BWP may be linked, for example,if a downlink BWP index of the downlink BWP and an uplink BWP index ofthe uplink BWP are the same. A wireless device may expect that thecenter frequency for a downlink BWP is the same as the center frequencyfor an uplink BWP (e.g., for unpaired spectra).

A base station may configure a wireless device with one or more controlresource sets (CORESETs) for at least one search space. The base stationmay configure the wireless device with one or more CORESETS, forexample, for a downlink BWP in a set of configured downlink BWPs on aprimary cell (PCell) or on a secondary cell (SCell). A search space maycomprise a set of locations in the time and frequency domains where thewireless device may monitor/find/detect/identify control information.The search space may be a wireless device-specific search space (e.g., aUE-specific search space) or a common search space (e.g., potentiallyusable by a plurality of wireless devices or a group of wireless userdevices). A base station may configure a group of wireless devices witha common search space, on a PCell or on a primary secondary cell(PSCell), in an active downlink BWP.

A base station may configure a wireless device with one or more resourcesets for one or more PUCCH transmissions, for example, for an uplink BWPin a set of configured uplink BWPs. A wireless device may receivedownlink receptions (e.g., PDCCH or PDSCH) in a downlink BWP, forexample, according to a configured numerology (e.g., a configuredsubcarrier spacing and/or a configured cyclic prefix duration) for thedownlink BWP. The wireless device may send/transmit uplink transmissions(e.g., PUCCH or PUSCH) in an uplink BWP, for example, according to aconfigured numerology (e.g., a configured subcarrier spacing and/or aconfigured cyclic prefix length for the uplink BWP).

One or more BWP indicator fields may be provided/comprised in DownlinkControl Information (DCI). A value of a BWP indicator field may indicatewhich BWP in a set of configured BWPs is an active downlink BWP for oneor more downlink receptions. The value of the one or more BWP indicatorfields may indicate an active uplink BWP for one or more uplinktransmissions.

A base station may semi-statically configure a wireless device with adefault downlink BWP within a set of configured downlink BWPs associatedwith a PCell. A default downlink BWP may be an initial active downlinkBWP, for example, if the base station does not provide/configure adefault downlink BWP to/for the wireless device. The wireless device maydetermine which BWP is the initial active downlink BWP, for example,based on a CORESET configuration obtained using the PBCH.

A base station may configure a wireless device with a BWP inactivitytimer value for a PCell. The wireless device may start or restart a BWPinactivity timer at any appropriate time. The wireless device may startor restart the BWP inactivity timer, for example, if one or moreconditions are satisfied. The one or more conditions may comprise atleast one of: the wireless device detects DCI indicating an activedownlink BWP other than a default downlink BWP for a paired spectraoperation; the wireless device detects DCI indicating an active downlinkBWP other than a default downlink BWP for an unpaired spectra operation;and/or the wireless device detects DCI indicating an active uplink BWPother than a default uplink BWP for an unpaired spectra operation. Thewireless device may start/run the BWP inactivity timer toward expiration(e.g., increment from zero to the BWP inactivity timer value, ordecrement from the BWP inactivity timer value to zero), for example, ifthe wireless device does not detect DCI during a time interval (e.g., 1ms or 0.5 ms). The wireless device may switch from the active downlinkBWP to the default downlink BWP, for example, if the BWP inactivitytimer expires.

A base station may semi-statically configure a wireless device with oneor more BWPs. A wireless device may switch an active BWP from a firstBWP to a second BWP, for example, after or in response to receiving DCIindicating the second BWP as an active BWP. A wireless device may switchan active BWP from a first BWP to a second BWP, for example, after or inresponse to an expiry of the BWP inactivity timer (e.g., if the secondBWP is the default BWP).

A downlink BWP switching may refer to switching an active downlink BWPfrom a first downlink BWP to a second downlink BWP (e.g., the seconddownlink BWP is activated and the first downlink BWP is deactivated). Anuplink BWP switching may refer to switching an active uplink BWP from afirst uplink BWP to a second uplink BWP (e.g., the second uplink BWP isactivated and the first uplink BWP is deactivated). Downlink and uplinkBWP switching may be performed independently (e.g., in pairedspectrum/spectra). Downlink and uplink BWP switching may be performedsimultaneously (e.g., in unpaired spectrum/spectra). Switching betweenconfigured BWPs may occur, for example, based on RRC signaling, DCIsignaling, expiration of a BWP inactivity timer, and/or an initiation ofrandom access.

FIG. 9 shows an example of configured BWPs. Bandwidth adaptation usingmultiple BWPs (e.g., three configured BWPs for an NR carrier) may beavailable. A wireless device configured with multiple BWPs (e.g., thethree BWPs) may switch from one BWP to another BWP at a switching point.The BWPs may comprise: a BWP 902 having a bandwidth of 40 MHz and asubcarrier spacing of 15 kHz; a BWP 904 having a bandwidth of 10 MHz anda subcarrier spacing of 15 kHz; and a BWP 906 having a bandwidth of 20MHz and a subcarrier spacing of 60 kHz. The BWP 902 may be an initialactive BWP, and the BWP 904 may be a default BWP. The wireless devicemay switch between BWPs at switching points. The wireless device mayswitch from the BWP 902 to the BWP 904 at a switching point 908. Theswitching at the switching point 908 may occur for any suitable reasons.The switching at a switching point 908 may occur, for example, after orin response to an expiry of a BWP inactivity timer (e.g., indicatingswitching to the default BWP). The switching at the switching point 908may occur, for example, after or in response to receiving DCI indicatingBWP 904 as the active BWP. The wireless device may switch at a switchingpoint 910 from an active BWP 904 to the BWP 906, for example, after orin response receiving DCI indicating BWP 906 as a new active BWP. Thewireless device may switch at a switching point 912 from an active BWP906 to the BWP 904, for example, after or in response to an expiry of aBWP inactivity timer. The wireless device may switch at the switchingpoint 912 from an active BWP 906 to the BWP 904, for example, after orin response receiving DCI indicating BWP 904 as a new active BWP. Thewireless device may switch at a switching point 914 from an active BWP904 to the BWP 902, for example, after or in response receiving DCIindicating the BWP 902 as a new active BWP.

Wireless device procedures for switching BWPs on a secondary cell may bethe same/similar as those on a primary cell, for example, if thewireless device is configured for a secondary cell with a defaultdownlink BWP in a set of configured downlink BWPs and a timer value. Thewireless device may use the timer value and the default downlink BWP forthe secondary cell in the same/similar manner as the wireless deviceuses the timer value and/or default BWPs for a primary cell. The timervalue (e.g., the BWP inactivity timer) may be configured per cell (e.g.,for one or more BWPs), for example, via RRC signaling or any othersignaling. One or more active BWPs may switch to another BWP, forexample, based on an expiration of the BWP inactivity timer.

Two or more carriers may be aggregated and data may be simultaneouslytransmitted to/from the same wireless device using carrier aggregation(CA) (e.g., to increase data rates). The aggregated carriers in CA maybe referred to as component carriers (CCs). There may be anumber/quantity of serving cells for the wireless device (e.g., oneserving cell for a CC), for example, if CA is configured/used. The CCsmay have multiple configurations in the frequency domain.

FIG. 10A shows example CA configurations based on CCs. As shown in FIG.10A, three types of CA configurations may comprise an intraband(contiguous) configuration 1002, an intraband (non-contiguous)configuration 1004, and/or an interband configuration 1006. In theintraband (contiguous) configuration 1002, two CCs may be aggregated inthe same frequency band (frequency band A) and may be located directlyadjacent to each other within the frequency band. In the intraband(non-contiguous) configuration 1004, two CCs may be aggregated in thesame frequency band (frequency band A) but may be separated from eachother in the frequency band by a gap. In the interband configuration1006, two CCs may be located in different frequency bands (e.g.,frequency band A and frequency band B, respectively).

A network may set the maximum quantity of CCs that can be aggregated(e.g., up to 32 CCs may be aggregated in NR, or any other quantity maybe aggregated in other systems). The aggregated CCs may have the same ordifferent bandwidths, subcarrier spacing, and/or duplexing schemes (TDD,FDD, or any other duplexing schemes). A serving cell for a wirelessdevice using CA may have a downlink CC. One or more uplink CCs may beoptionally configured for a serving cell (e.g., for FDD). The ability toaggregate more downlink carriers than uplink carriers may be useful, forexample, if the wireless device has more data traffic in the downlinkthan in the uplink.

One of the aggregated cells for a wireless device may be referred to asa primary cell (PCell), for example, if a CA is configured. The PCellmay be the serving cell that the wireless initially connects to oraccess to, for example, during or at an RRC connection establishment, anRRC connection reestablishment, and/or a handover. The PCell mayprovide/configure the wireless device with NAS mobility information andthe security input. Wireless device may have different PCells. For thedownlink, the carrier corresponding to the PCell may be referred to asthe downlink primary CC (DL PCC). For the uplink, the carriercorresponding to the PCell may be referred to as the uplink primary CC(UL PCC). The other aggregated cells (e.g., associated with CCs otherthan the DL PCC and UL PCC) for the wireless device may be referred toas secondary cells (SCells). The SCells may be configured, for example,after the PCell is configured for the wireless device. An SCell may beconfigured via an RRC connection reconfiguration procedure. For thedownlink, the carrier corresponding to an SCell may be referred to as adownlink secondary CC (DL SCC). For the uplink, the carriercorresponding to the SCell may be referred to as the uplink secondary CC(UL SCC).

Configured SCells for a wireless device may be activated or deactivated,for example, based on traffic and channel conditions. Deactivation of anSCell may cause the wireless device to stop PDCCH and PDSCH reception onthe SCell and PUSCH, SRS, and CQI transmissions on the SCell. ConfiguredSCells may be activated or deactivated, for example, using a MAC CE(e.g., the MAC CE described with respect to FIG. 4B). A MAC CE may use abitmap (e.g., one bit per SCell) to indicate which SCells (e.g., in asubset of configured SCells) for the wireless device are activated ordeactivated. Configured SCells may be deactivated, for example, after orin response to an expiration of an SCell deactivation timer (e.g., oneSCell deactivation timer per SCell may be configured).

DCI may comprise control information, such as scheduling assignments andscheduling grants, for a cell. DCI may be sent/transmitted via the cellcorresponding to the scheduling assignments and/or scheduling grants,which may be referred to as a self-scheduling. DCI comprising controlinformation for a cell may be sent/transmitted via another cell, whichmay be referred to as a cross-carrier scheduling. Uplink controlinformation (UCI) may comprise control information, such as HARQacknowledgments and channel state feedback (e.g., CQI, PMI, and/or RI)for aggregated cells. UCI may be transmitted via an uplink controlchannel (e.g., a PUCCH) of the PCell or a certain SCell (e.g., an SCellconfigured with PUCCH). For a larger number of aggregated downlink CCs,the PUCCH of the PCell may become overloaded. Cells may be divided intomultiple PUCCH groups.

FIG. 10B shows example group of cells. Aggregated cells may beconfigured into one or more PUCCH groups (e.g., as shown in FIG. 10B).One or more cell groups or one or more uplink control channel groups(e.g., a PUCCH group 1010 and a PUCCH group 1050) may comprise one ormore downlink CCs, respectively. The PUCCH group 1010 may comprise oneor more downlink CCs, for example, three downlink CCs: a PCell 1011(e.g., a DL PCC), an SCell 1012 (e.g., a DL SCC), and an SCell 1013(e.g., a DL SCC). The PUCCH group 1050 may comprise one or more downlinkCCs, for example, three downlink CCs: a PUCCH SCell (or PSCell) 1051(e.g., a DL SCC), an SCell 1052 (e.g., a DL SCC), and an SCell 1053(e.g., a DL SCC). One or more uplink CCs of the PUCCH group 1010 may beconfigured as a PCell 1021 (e.g., a UL PCC), an SCell 1022 (e.g., a ULSCC), and an SCell 1023 (e.g., a UL SCC). One or more uplink CCs of thePUCCH group 1050 may be configured as a PUCCH SCell (or PSCell) 1061(e.g., a UL SCC), an SCell 1062 (e.g., a UL SCC), and an SCell 1063(e.g., a UL SCC). UCI related to the downlink CCs of the PUCCH group1010, shown as UCI 1031, UCI 1032, and UCI 1033, may be transmitted viathe uplink of the PCell 1021 (e.g., via the PUCCH of the PCell 1021).UCI related to the downlink CCs of the PUCCH group 1050, shown as UCI1071, UCI 1072, and UCI 1073, may be sent/transmitted via the uplink ofthe PUCCH SCell (or PSCell) 1061 (e.g., via the PUCCH of the PUCCH SCell1061). A single uplink PCell may be configured to send/transmit UCIrelating to the six downlink CCs, for example, if the aggregated cellsshown in FIG. 10B are not divided into the PUCCH group 1010 and thePUCCH group 1050. The PCell 1021 may become overloaded, for example, ifthe UCIs 1031, 1032, 1033, 1071, 1072, and 1073 are sent/transmitted viathe PCell 1021. By dividing transmissions of UCI between the PCell 1021and the PUCCH SCell (or PSCell) 1061, overloading may be preventedand/or reduced.

A PCell may comprise a downlink carrier (e.g., the PCell 1011) and anuplink carrier (e.g., the PCell 1021). An SCell may comprise only adownlink carrier. A cell, comprising a downlink carrier and optionallyan uplink carrier, may be assigned with a physical cell ID and a cellindex. The physical cell ID or the cell index may indicate/identify adownlink carrier and/or an uplink carrier of the cell, for example,depending on the context in which the physical cell ID is used. Aphysical cell ID may be determined, for example, using a synchronizationsignal (e.g., PSS and/or SSS) transmitted via a downlink componentcarrier. A cell index may be determined, for example, using one or moreRRC messages. A physical cell ID may be referred to as a carrier ID, anda cell index may be referred to as a carrier index. A first physicalcell ID for a first downlink carrier may refer to the first physicalcell ID for a cell comprising the first downlink carrier. Substantiallythe same/similar concept may apply to, for example, a carrieractivation. Activation of a first carrier may refer to activation of acell comprising the first carrier.

A multi-carrier nature of a PHY layer may be exposed/indicated to a MAClayer (e.g., in a CA configuration). A HARQ entity may operate on aserving cell. A transport block may be generated per assignment/grantper serving cell. A transport block and potential HARQ retransmissionsof the transport block may be mapped to a serving cell.

For the downlink, a base station may send/transmit (e.g., unicast,multicast, and/or broadcast), to one or more wireless devices, one ormore reference signals (RSs) (e.g., PSS, SSS, CSI-RS, DM-RS, and/orPT-RS). For the uplink, the one or more wireless devices maysend/transmit one or more RSs to the base station (e.g., DM-RS, PT-RS,and/or SRS). The PSS and the SSS may be sent/transmitted by the basestation and used by the one or more wireless devices to synchronize theone or more wireless devices with the base station. A synchronizationsignal (SS)/physical broadcast channel (PBCH) block may comprise thePSS, the SSS, and the PBCH. The base station may periodicallysend/transmit a burst of SS/PBCH blocks, which may be referred to asSSBs.

FIG. 11A shows an example mapping of one or more SS/PBCH blocks. A burstof SS/PBCH blocks may comprise one or more SS/PBCH blocks (e.g., 4SS/PBCH blocks, as shown in FIG. 11A). Bursts may be sent/transmittedperiodically (e.g., every 2 frames, 20 ms, or any other durations). Aburst may be restricted to a half-frame (e.g., a first half-frame havinga duration of 5 ms). Such parameters (e.g., the number of SS/PBCH blocksper burst, periodicity of bursts, position of the burst within theframe) may be configured, for example, based on at least one of: acarrier frequency of a cell in which the SS/PBCH block issent/transmitted; a numerology or subcarrier spacing of the cell; aconfiguration by the network (e.g., using RRC signaling); and/or anyother suitable factor(s). A wireless device may assume a subcarrierspacing for the SS/PBCH block based on the carrier frequency beingmonitored, for example, unless the radio network configured the wirelessdevice to assume a different subcarrier spacing.

The SS/PBCH block may span one or more OFDM symbols in the time domain(e.g., 4 OFDM symbols, as shown in FIG. 11A or any other quantity/numberof symbols) and may span one or more subcarriers in the frequency domain(e.g., 240 contiguous subcarriers or any other quantity/number ofsubcarriers). The PSS, the SSS, and the PBCH may have a common centerfrequency. The PSS may be sent/transmitted first and may span, forexample, 1 OFDM symbol and 127 subcarriers. The SSS may besent/transmitted after the PSS (e.g., two symbols later) and may span 1OFDM symbol and 127 subcarriers. The PBCH may be sent/transmitted afterthe PSS (e.g., across the next 3 01-DM symbols) and may span 240subcarriers (e.g., in the second and fourth OFDM symbols as shown inFIG. 11A) and/or may span fewer than 240 subcarriers (e.g., in the thirdOFDM symbols as shown in FIG. 11A).

The location of the SS/PBCH block in the time and frequency domains maynot be known to the wireless device (e.g., if the wireless device issearching for the cell). The wireless device may monitor a carrier forthe PSS, for example, to find and select the cell. The wireless devicemay monitor a frequency location within the carrier. The wireless devicemay search for the PSS at a different frequency location within thecarrier, for example, if the PSS is not found after a certain duration(e.g., 20 ms). The wireless device may search for the PSS at a differentfrequency location within the carrier, for example, as indicated by asynchronization raster. The wireless device may determine the locationsof the SSS and the PBCH, respectively, for example, based on a knownstructure of the SS/PBCH block if the PSS is found at a location in thetime and frequency domains. The SS/PBCH block may be a cell-defining SSblock (CD-SSB). A primary cell may be associated with a CD-SSB. TheCD-SSB may be located on a synchronization raster. A cellselection/search and/or reselection may be based on the CD-SSB.

The SS/PBCH block may be used by the wireless device to determine one ormore parameters of the cell. The wireless device may determine aphysical cell identifier (PCI) of the cell, for example, based on thesequences of the PSS and the SSS, respectively. The wireless device maydetermine a location of a frame boundary of the cell, for example, basedon the location of the SS/PBCH block. The SS/PBCH block may indicatethat it has been sent/transmitted in accordance with a transmissionpattern. An SS/PBCH block in the transmission pattern may be a knowndistance from the frame boundary (e.g., a predefined distance for a RANconfiguration among one or more networks, one or more base stations, andone or more wireless devices).

The PBCH may use a QPSK modulation and/or forward error correction(FEC). The FEC may use polar coding. One or more symbols spanned by thePBCH may comprise/carry one or more DM-RSs for demodulation of the PBCH.The PBCH may comprise an indication of a current system frame number(SFN) of the cell and/or a SS/PBCH block timing index. These parametersmay facilitate time synchronization of the wireless device to the basestation. The PBCH may comprise a MIB used to send/transmit to thewireless device one or more parameters. The MIB may be used by thewireless device to locate remaining minimum system information (RMSI)associated with the cell. The RMSI may comprise a System InformationBlock Type 1 (SIB 1). The SIB 1 may comprise information for thewireless device to access the cell. The wireless device may use one ormore parameters of the MIB to monitor a PDCCH, which may be used toschedule a PDSCH. The PDSCH may comprise the SIB 1. The SIB1 may bedecoded using parameters provided/comprised in the MIB. The PBCH mayindicate an absence of SIB 1. The wireless device may be pointed to afrequency, for example, based on the PBCH indicating the absence ofSIB1. The wireless device may search for an SS/PBCH block at thefrequency to which the wireless device is pointed.

The wireless device may assume that one or more SS/PBCH blockssent/transmitted with a same SS/PBCH block index are quasi co-located(QCLed) (e.g., having substantially the same/similar Doppler spread,Doppler shift, average gain, average delay, and/or spatial Rxparameters). The wireless device may not assume QCL for SS/PBCH blocktransmissions having different SS/PBCH block indices. SS/PBCH blocks(e.g., those within a half-frame) may be sent/transmitted in spatialdirections (e.g., using different beams that span a coverage area of thecell). A first SS/PBCH block may be sent/transmitted in a first spatialdirection using a first beam, a second SS/PBCH block may besent/transmitted in a second spatial direction using a second beam, athird SS/PBCH block may be sent/transmitted in a third spatial directionusing a third beam, a fourth SS/PBCH block may be sent/transmitted in afourth spatial direction using a fourth beam, etc.

A base station may send/transmit a plurality of SS/PBCH blocks, forexample, within a frequency span of a carrier. A first PCI of a firstSS/PBCH block of the plurality of SS/PBCH blocks may be different from asecond PCI of a second SS/PBCH block of the plurality of SS/PBCH blocks.The PCIs of SS/PBCH blocks sent/transmitted in different frequencylocations may be different or substantially the same.

The CSI-RS may be sent/transmitted by the base station and used by thewireless device to acquire/obtain/determine channel state information(CSI). The base station may configure the wireless device with one ormore CSI-RSs for channel estimation or any other suitable purpose. Thebase station may configure a wireless device with one or more of thesame/similar CSI-RSs. The wireless device may measure the one or moreCSI-RSs. The wireless device may estimate a downlink channel stateand/or generate a CSI report, for example, based on the measuring of theone or more downlink CSI-RSs. The wireless device may send/transmit theCSI report to the base station (e.g., based on periodic CSI reporting,semi-persistent CSI reporting, and/or aperiodic CSI reporting). The basestation may use feedback provided by the wireless device (e.g., theestimated downlink channel state) to perform a link adaptation.

The base station may semi-statically configure the wireless device withone or more CSI-RS resource sets. A CSI-RS resource may be associatedwith a location in the time and frequency domains and a periodicity. Thebase station may selectively activate and/or deactivate a CSI-RSresource. The base station may indicate to the wireless device that aCSI-RS resource in the CSI-RS resource set is activated and/ordeactivated.

The base station may configure the wireless device to report CSImeasurements. The base station may configure the wireless device toprovide CSI reports periodically, aperiodically, or semi-persistently.For periodic CSI reporting, the wireless device may be configured with atiming and/or periodicity of a plurality of CSI reports. For aperiodicCSI reporting, the base station may request a CSI report. The basestation may command the wireless device to measure a configured CSI-RSresource and provide a CSI report relating to the measurement(s). Forsemi-persistent CSI reporting, the base station may configure thewireless device to send/transmit periodically, and selectively activateor deactivate the periodic reporting (e.g., via one or moreactivation/deactivation MAC CEs and/or one or more DCIs). The basestation may configure the wireless device with a CSI-RS resource set andCSI reports, for example, using RRC signaling.

The CSI-RS configuration may comprise one or more parameters indicating,for example, up to 32 antenna ports (or any other quantity of antennaports). The wireless device may be configured to use/employ the sameOFDM symbols for a downlink CSI-RS and a CORESET, for example, if thedownlink CSI-RS and CORESET are spatially QCLed and resource elementsassociated with the downlink CSI-RS are outside of the physical resourceblocks (PRBs) configured for the CORESET. The wireless device may beconfigured to use/employ the same OFDM symbols for a downlink CSI-RS andSS/PBCH blocks, for example, if the downlink CSI-RS and SS/PBCH blocksare spatially QCLed and resource elements associated with the downlinkCSI-RS are outside of PRBs configured for the SS/PBCH blocks.

Downlink DM-RSs may be sent/transmitted by a base station andreceived/used by a wireless device for a channel estimation. Thedownlink DM-RSs may be used for coherent demodulation of one or moredownlink physical channels (e.g., PDSCH). A network (e.g., an NRnetwork) may support one or more variable and/or configurable DM-RSpatterns for data demodulation. At least one downlink DM-RSconfiguration may support a front-loaded DM-RS pattern. A front-loadedDM-RS may be mapped over one or more OFDM symbols (e.g., one or twoadjacent OFDM symbols). A base station may semi-statically configure thewireless device with a number/quantity (e.g. a maximum number/quantity)of front-loaded DM-RS symbols for a PDSCH. A DM-RS configuration maysupport one or more DM-RS ports. A DM-RS configuration may support up toeight orthogonal downlink DM-RS ports per wireless device (e.g., forsingle user-MIMO). A DM-RS configuration may support up to 4 orthogonaldownlink DM-RS ports per wireless device (e.g., for multiuser-MIMO). Aradio network may support (e.g., at least for CP-OFDM) a common DM-RSstructure for downlink and uplink. A DM-RS location, a DM-RS pattern,and/or a scrambling sequence may be the same or different. The basestation may send/transmit a downlink DM-RS and a corresponding PDSCH,for example, using the same precoding matrix. The wireless device mayuse the one or more downlink DM-RSs for coherent demodulation/channelestimation of the PDSCH.

A transmitter (e.g., a transmitter of a base station) may use a precodermatrices for a part of a transmission bandwidth. The transmitter may usea first precoder matrix for a first bandwidth and a second precodermatrix for a second bandwidth. The first precoder matrix and the secondprecoder matrix may be different, for example, based on the firstbandwidth being different from the second bandwidth. The wireless devicemay assume that a same precoding matrix is used across a set of PRBs.The set of PRBs may be determined/indicated/identified/denoted as aprecoding resource block group (PRG).

A PDSCH may comprise one or more layers. The wireless device may assumethat at least one symbol with DM-RS is present on a layer of the one ormore layers of the PDSCH. A higher layer may configure one or moreDM-RSs for a PDSCH (e.g., up to 3 DMRSs for the PDSCH). Downlink PT-RSmay be sent/transmitted by a base station and used by a wireless device,for example, for a phase-noise compensation. Whether a downlink PT-RS ispresent or not may depend on an RRC configuration. The presence and/orthe pattern of the downlink PT-RS may be configured on a wirelessdevice-specific basis, for example, using a combination of RRC signalingand/or an association with one or more parameters used/employed forother purposes (e.g., modulation and coding scheme (MCS)), which may beindicated by DCI. A dynamic presence of a downlink PT-RS, if configured,may be associated with one or more DCI parameters comprising at leastMCS. A network (e.g., an NR network) may support a plurality of PT-RSdensities defined in the time and/or frequency domains. A frequencydomain density (if configured/present) may be associated with at leastone configuration of a scheduled bandwidth. The wireless device mayassume a same precoding for a DM-RS port and a PT-RS port. Thequantity/number of PT-RS ports may be fewer than the quantity/number ofDM-RS ports in a scheduled resource. Downlink PT-RS may beconfigured/allocated/confined in the scheduled time/frequency durationfor the wireless device. Downlink PT-RS may be sent/transmitted viasymbols, for example, to facilitate a phase tracking at the receiver.

The wireless device may send/transmit an uplink DM-RS to a base station,for example, for a channel estimation. The base station may use theuplink DM-RS for coherent demodulation of one or more uplink physicalchannels. The wireless device may send/transmit an uplink DM-RS with aPUSCH and/or a PUCCH. The uplink DM-RS may span a range of frequenciesthat is similar to a range of frequencies associated with thecorresponding physical channel The base station may configure thewireless device with one or more uplink DM-RS configurations. At leastone DM-RS configuration may support a front-loaded DM-RS pattern. Thefront-loaded DM-RS may be mapped over one or more OFDM symbols (e.g.,one or two adjacent OFDM symbols). One or more uplink DM-RSs may beconfigured to send/transmit at one or more symbols of a PUSCH and/or aPUCCH. The base station may semi-statically configure the wirelessdevice with a number/quantity (e.g. the maximum number/quantity) offront-loaded DM-RS symbols for the PUSCH and/or the PUCCH, which thewireless device may use to schedule a single-symbol DM-RS and/or adouble-symbol DM-RS. A network (e.g., an NR network) may support (e.g.,for cyclic prefix orthogonal frequency division multiplexing (CP-OFDM))a common DM-RS structure for downlink and uplink. A DM-RS location, aDM-RS pattern, and/or a scrambling sequence for the DM-RS may besubstantially the same or different.

A PUSCH may comprise one or more layers. A wireless device maysend/transmit at least one symbol with DM-RS present on a layer of theone or more layers of the PUSCH. A higher layer may configure one ormore DM-RSs (e.g., up to three DMRSs) for the PUSCH. Uplink PT-RS (whichmay be used by a base station for a phase tracking and/or a phase-noisecompensation) may or may not be present, for example, depending on anRRC configuration of the wireless device. The presence and/or thepattern of an uplink PT-RS may be configured on a wirelessdevice-specific basis (e.g., a UE-specific basis), for example, by acombination of RRC signaling and/or one or more parametersconfigured/employed for other purposes (e.g., MCS), which may beindicated by DCI. A dynamic presence of an uplink PT-RS, if configured,may be associated with one or more DCI parameters comprising at leastMCS. A radio network may support a plurality of uplink PT-RS densitiesdefined in time/frequency domain. A frequency domain density (ifconfigured/present) may be associated with at least one configuration ofa scheduled bandwidth. The wireless device may assume a same precodingfor a DM-RS port and a PT-RS port. A quantity/number of PT-RS ports maybe less than a quantity/number of DM-RS ports in a scheduled resource.An uplink PT-RS may be configured/allocated/confined in the scheduledtime/frequency duration for the wireless device.

One or more SRSs may be sent/transmitted by a wireless device to a basestation, for example, for a channel state estimation to support uplinkchannel dependent scheduling and/or a link adaptation. SRSsent/transmitted by the wireless device may enable/allow a base stationto estimate an uplink channel state at one or more frequencies. Ascheduler at the base station may use/employ the estimated uplinkchannel state to assign one or more resource blocks for an uplink PUSCHtransmission for the wireless device. The base station maysemi-statically configure the wireless device with one or more SRSresource sets. For an SRS resource set, the base station may configurethe wireless device with one or more SRS resources. An SRS resource setapplicability may be configured, for example, by a higher layer (e.g.,RRC) parameter. An SRS resource in a SRS resource set of the one or moreSRS resource sets (e.g., with the same/similar time domain behavior,periodic, aperiodic, and/or the like) may be sent/transmitted at a timeinstant (e.g., simultaneously), for example, if a higher layer parameterindicates beam management. The wireless device may send/transmit one ormore SRS resources in SRS resource sets. A network (e.g., an NR network)may support aperiodic, periodic, and/or semi-persistent SRStransmissions. The wireless device may send/transmit SRS resources, forexample, based on one or more trigger types. The one or more triggertypes may comprise higher layer signaling (e.g., RRC) and/or one or moreDCI formats. At least one DCI format may be used/employed for thewireless device to select at least one of one or more configured SRSresource sets. An SRS trigger type 0 may refer to an SRS triggered basedon higher layer signaling. An SRS trigger type 1 may refer to an SRStriggered based on one or more DCI formats. The wireless device may beconfigured to send/transmit an SRS, for example, after a transmission ofa PUSCH and a corresponding uplink DM-RS if a PUSCH and an SRS aresent/transmitted in a same slot. A base station may semi-staticallyconfigure a wireless device with one or more SRS configurationparameters indicating at least one of following: a SRS resourceconfiguration identifier; a number of SRS ports; time domain behavior ofan SRS resource configuration (e.g., an indication of periodic,semi-persistent, or aperiodic SRS); slot, mini-slot, and/or subframelevel periodicity; an offset for a periodic and/or an aperiodic SRSresource; a number of OFDM symbols in an SRS resource; a starting OFDMsymbol of an SRS resource; an SRS bandwidth; a frequency hoppingbandwidth; a cyclic shift; and/or an SRS sequence ID.

An antenna port may be determined/defined such that the channel overwhich a symbol on the antenna port is conveyed can be inferred from thechannel over which another symbol on the same antenna port is conveyed.The receiver may infer/determine the channel (e.g., fading gain,multipath delay, and/or the like) for conveying a second symbol on anantenna port, from the channel for conveying a first symbol on theantenna port, for example, if the first symbol and the second symbol aresent/transmitted on the same antenna port. A first antenna port and asecond antenna port may be referred to as quasi co-located (QCLed), forexample, if one or more large-scale properties of the channel over whicha first symbol on the first antenna port is conveyed may be inferredfrom the channel over which a second symbol on a second antenna port isconveyed. The one or more large-scale properties may comprise at leastone of: a delay spread; a Doppler spread; a Doppler shift; an averagegain; an average delay; and/or spatial receiving (Rx) parameters.

Channels that use beamforming may require beam management. Beammanagement may comprise a beam measurement, a beam selection, and/or abeam indication. A beam may be associated with one or more referencesignals. A beam may be identified by one or more beamformed referencesignals. The wireless device may perform a downlink beam measurement,for example, based on one or more downlink reference signals (e.g., aCSI-RS) and generate a beam measurement report. The wireless device mayperform the downlink beam measurement procedure, for example, after anRRC connection is set up with a base station.

FIG. 11B shows an example mapping of one or more CSI-RSs. The CSI-RSsmay be mapped in the time and frequency domains. Each rectangular blockshown in FIG. 11B may correspond to a resource block (RB) within abandwidth of a cell. A base station may send/transmit one or more RRCmessages comprising CSI-RS resource configuration parameters indicatingone or more CSI-RSs. One or more of parameters may be configured byhigher layer signaling (e.g., RRC and/or MAC signaling) for a CSI-RSresource configuration. The one or more of the parameters may compriseat least one of: a CSI-RS resource configuration identity, a number ofCSI-RS ports, a CSI-RS configuration (e.g., symbol and resource element(RE) locations in a subframe), a CSI-RS subframe configuration (e.g., asubframe location, an offset, and periodicity in a radio frame), aCSI-RS power parameter, a CSI-RS sequence parameter, a code divisionmultiplexing (CDM) type parameter, a frequency density, a transmissioncomb, quasi co-location (QCL) parameters (e.g., QCL-scramblingidentity,crs-portscount, mbsfn-subframeconfiglist, csi-rs-configZPid,qcl-csi-rs-configNZPid), and/or other radio resource parameters.

One or more beams may be configured for a wireless device in a wirelessdevice-specific configuration. Three beams are shown in FIG. 11B (beam #1, beam # 2, and beam # 3), but more or fewer beams may be configured.Beam # 1 may be allocated with CSI-RS 1101 that may be sent/transmittedin one or more subcarriers in an RB of a first symbol. Beam # 2 may beallocated with CSI-RS 1102 that may be sent/transmitted in one or moresubcarriers in an RB of a second symbol. Beam # 3 may be allocated withCSI-RS 1103 that may be sent/transmitted in one or more subcarriers inan RB of a third symbol. A base station may use other subcarriers in thesame RB (e.g., those that are not used to send/transmit CSI-RS 1101) totransmit another CSI-RS associated with a beam for another wirelessdevice, for example, by using frequency division multiplexing (FDM).Beams used for a wireless device may be configured such that beams forthe wireless device use symbols different from symbols used by beams ofother wireless devices, for example, by using time domain multiplexing(TDM). A wireless device may be served with beams in orthogonal symbols(e.g., no overlapping symbols), for example, by using the TDM.

CSI-RSs (e.g., CSI-RSs 1101, 1102, 1103) may be sent/transmitted by thebase station and used by the wireless device for one or moremeasurements. The wireless device may measure an RSRP of configuredCSI-RS resources. The base station may configure the wireless devicewith a reporting configuration, and the wireless device may report theRSRP measurements to a network (e.g., via one or more base stations)based on the reporting configuration. The base station may determine,based on the reported measurement results, one or more transmissionconfiguration indication (TCI) states comprising a number of referencesignals. The base station may indicate one or more TCI states to thewireless device (e.g., via RRC signaling, a MAC CE, and/or DCI). Thewireless device may receive a downlink transmission with an Rx beamdetermined based on the one or more TCI states. The wireless device mayor may not have a capability of beam correspondence. The wireless devicemay determine a spatial domain filter of a transmit (Tx) beam, forexample, based on a spatial domain filter of the corresponding Rx beam,if the wireless device has the capability of beam correspondence. Thewireless device may perform an uplink beam selection procedure todetermine the spatial domain filter of the Tx beam, for example, if thewireless device does not have the capability of beam correspondence. Thewireless device may perform the uplink beam selection procedure, forexample, based on one or more sounding reference signal (SRS) resourcesconfigured to the wireless device by the base station. The base stationmay select and indicate uplink beams for the wireless device, forexample, based on measurements of the one or more SRS resourcessent/transmitted by the wireless device.

A wireless device may determine/assess (e.g., measure) a channel qualityof one or more beam pair links, for example, in a beam managementprocedure. A beam pair link may comprise a Tx beam of a base station andan Rx beam of the wireless device. The Tx beam of the base station maysend/transmit a downlink signal, and the Rx beam of the wireless devicemay receive the downlink signal. The wireless device may send/transmit abeam measurement report, for example, based on theassessment/determination. The beam measurement report may indicate oneor more beam pair quality parameters comprising at least one of: one ormore beam identifications (e.g., a beam index, a reference signal index,or the like), an RSRP, a precoding matrix indicator (PMI), a channelquality indicator (CQI), and/or a rank indicator (RI).

FIG. 12A shows examples of downlink beam management procedures. One ormore downlink beam management procedures (e.g., downlink beam managementprocedures P1, P2, and P3) may be performed. Procedure P1 may enable ameasurement (e.g., a wireless device measurement) on Tx beams of a TRP(or multiple TRPs) (e.g., to support a selection of one or more basestation Tx beams and/or wireless device Rx beams). The Tx beams of abase station and the Rx beams of a wireless device are shown as ovals inthe top row of P1 and bottom row of P1, respectively. Beamforming (e.g.,at a TRP) may comprise a Tx beam sweep for a set of beams (e.g., thebeam sweeps shown, in the top rows of P1 and P2, as ovals rotated in acounter-clockwise direction indicated by the dashed arrows). Beamforming(e.g., at a wireless device) may comprise an Rx beam sweep for a set ofbeams (e.g., the beam sweeps shown, in the bottom rows of P1 and P3, asovals rotated in a clockwise direction indicated by the dashed arrows).Procedure P2 may be used to enable a measurement (e.g., a wirelessdevice measurement) on Tx beams of a TRP (shown, in the top row of P2,as ovals rotated in a counter-clockwise direction indicated by thedashed arrow). The wireless device and/or the base station may performprocedure P2, for example, using a smaller set of beams than the set ofbeams used in procedure P1, or using narrower beams than the beams usedin procedure P1. Procedure P2 may be referred to as a beam refinement.The wireless device may perform procedure P3 for an Rx beamdetermination, for example, by using the same Tx beam(s) of the basestation and sweeping Rx beam(s) of the wireless device.

FIG. 12B shows examples of uplink beam management procedures. One ormore uplink beam management procedures (e.g., uplink beam managementprocedures U1, U2, and U3) may be performed. Procedure U1 may be used toenable a base station to perform a measurement on Tx beams of a wirelessdevice (e.g., to support a selection of one or more Tx beams of thewireless device and/or Rx beams of the base station). The Tx beams ofthe wireless device and the Rx beams of the base station are shown asovals in the top row of U1 and bottom row of U1, respectively).Beamforming (e.g., at the wireless device) may comprise one or more beamsweeps, for example, a Tx beam sweep from a set of beams (shown, in thebottom rows of U1 and U3, as ovals rotated in a clockwise directionindicated by the dashed arrows). Beamforming (e.g., at the base station)may comprise one or more beam sweeps, for example, an Rx beam sweep froma set of beams (shown, in the top rows of U1 and U2, as ovals rotated ina counter-clockwise direction indicated by the dashed arrows). ProcedureU2 may be used to enable the base station to adjust its Rx beam, forexample, if the UE uses a fixed Tx beam. The wireless device and/or thebase station may perform procedure U2, for example, using a smaller setof beams than the set of beams used in procedure P1, or using narrowerbeams than the beams used in procedure P1. Procedure U2 may be referredto as a beam refinement. The wireless device may perform procedure U3 toadjust its Tx beam, for example, if the base station uses a fixed Rxbeam.

A wireless device may initiate/start/perform a beam failure recovery(BFR) procedure, for example, based on detecting a beam failure. Thewireless device may send/transmit a BFR request (e.g., a preamble, UCI,an SR, a MAC CE, and/or the like), for example, based on the initiatingthe BFR procedure. The wireless device may detect the beam failure, forexample, based on a determination that a quality of beam pair link(s) ofan associated control channel is unsatisfactory (e.g., having an errorrate higher than an error rate threshold, a received signal power lowerthan a received signal power threshold, an expiration of a timer, and/orthe like).

The wireless device may measure a quality of a beam pair link, forexample, using one or more reference signals (RSs) comprising one ormore SS/PBCH blocks, one or more CSI-RS resources, and/or one or moreDM-RSs. A quality of the beam pair link may be based on one or more of ablock error rate (BLER), an RSRP value, a signal to interference plusnoise ratio (SINR) value, an RSRQ value, and/or a CSI value measured onRS resources. The base station may indicate that an RS resource is QCLedwith one or more DM-RSs of a channel (e.g., a control channel, a shareddata channel, and/or the like). The RS resource and the one or moreDM-RSs of the channel may be QCLed, for example, if the channelcharacteristics (e.g., Doppler shift, Doppler spread, an average delay,delay spread, a spatial Rx parameter, fading, and/or the like) from atransmission via the RS resource to the wireless device are similar orthe same as the channel characteristics from a transmission via thechannel to the wireless device.

A network (e.g., an NR network comprising a gNB and/or an ng-eNB) and/orthe wireless device may initiate/start/perform a random accessprocedure. A wireless device in an RRC idle (e.g., an RRC_IDLE) stateand/or an RRC inactive (e.g., an RRC_INACTIVE) state mayinitiate/perform the random access procedure to request a connectionsetup to a network. The wireless device may initiate/start/perform therandom access procedure from an RRC connected (e.g., an RRC_CONNECTED)state. The wireless device may initiate/start/perform the random accessprocedure to request uplink resources (e.g., for uplink transmission ofan SR if there is no PUCCH resource available) and/oracquire/obtain/determine an uplink timing (e.g., if an uplinksynchronization status is non-synchronized). The wireless device mayinitiate/start/perform the random access procedure to request one ormore system information blocks (SIBs) (e.g., other system informationblocks, such as SIB2, SIB3, and/or the like). The wireless device mayinitiate/start/perform the random access procedure for a beam failurerecovery request. A network may initiate/start/perform a random accessprocedure, for example, for a handover and/or for establishing timealignment for an SCell addition.

FIG. 13A shows an example four-step random access procedure. Thefour-step random access procedure may comprise a four-stepcontention-based random access procedure. A base station maysend/transmit a configuration message 1310 to a wireless device, forexample, before initiating the random access procedure. The four-steprandom access procedure may comprise transmissions of four messagescomprising: a first message (e.g., Msg 1 1311), a second message (e.g.,Msg 2 1312), a third message (e.g., Msg 3 1313), and a fourth message(e.g., Msg 4 1314). The first message (e.g., Msg 1 1311) may comprise apreamble (or a random access preamble). The first message (e.g., Msg 11311) may be referred to as a preamble. The second message (e.g., Msg 21312) may comprise as a random access response (RAR). The second message(e.g., Msg 2 1312) may be referred to as an RAR.

The configuration message 1310 may be sent/transmitted, for example,using one or more RRC messages. The one or more RRC messages mayindicate one or more random access channel (RACH) parameters to thewireless device. The one or more RACH parameters may comprise at leastone of: general parameters for one or more random access procedures(e.g., RACH-configGeneral); cell-specific parameters (e.g.,RACH-ConfigCommon); and/or dedicated parameters (e.g.,RACH-configDedicated). The base station may send/transmit (e.g.,broadcast or multicast) the one or more RRC messages to one or morewireless devices. The one or more RRC messages may be wirelessdevice-specific. The one or more RRC messages that are wirelessdevice-specific may be, for example, dedicated RRC messagessent/transmitted to a wireless device in an RRC connected (e.g., anRRC_CONNECTED) state and/or in an RRC inactive (e.g., an RRC_INACTIVE)state. The wireless devices may determine, based on the one or more RACHparameters, a time-frequency resource and/or an uplink transmit powerfor transmission of the first message (e.g., Msg 1 1311) and/or thethird message (e.g., Msg 3 1313). The wireless device may determine areception timing and a downlink channel for receiving the second message(e.g., Msg 2 1312) and the fourth message (e.g., Msg 4 1314), forexample, based on the one or more RACH parameters.

The one or more RACH parameters provided/configured/comprised in theconfiguration message 1310 may indicate one or more Physical RACH(PRACH) occasions available for transmission of the first message (e.g.,Msg 1 1311). The one or more PRACH occasions may be predefined (e.g., bya network comprising one or more base stations). The one or more RACHparameters may indicate one or more available sets of one or more PRACHoccasions (e.g., prach-Configlndex). The one or more RACH parameters mayindicate an association between (a) one or more PRACH occasions and (b)one or more reference signals. The one or more RACH parameters mayindicate an association between (a) one or more preambles and (b) one ormore reference signals. The one or more reference signals may be SS/PBCHblocks and/or CSI-RSs. The one or more RACH parameters may indicate aquantity/number of SS/PBCH blocks mapped to a PRACH occasion and/or aquantity/number of preambles mapped to a SS/PBCH blocks.

The one or more RACH parameters provided/configured/comprised in theconfiguration message 1310 may be used to determine an uplink transmitpower of first message (e.g., Msg 1 1311) and/or third message (e.g.,Msg 3 1313). The one or more RACH parameters may indicate a referencepower for a preamble transmission (e.g., a received target power and/oran initial power of the preamble transmission). There may be one or morepower offsets indicated by the one or more RACH parameters. The one ormore RACH parameters may indicate: a power ramping step; a power offsetbetween SSB and CSI-RS; a power offset between transmissions of thefirst message (e.g., Msg 1 1311) and the third message (e.g., Msg 31313); and/or a power offset value between preamble groups. The one ormore RACH parameters may indicate one or more thresholds, for example,based on which the wireless device may determine at least one referencesignal (e.g., an SSB and/or CSI-RS) and/or an uplink carrier (e.g., anormal uplink (NUL) carrier and/or a supplemental uplink (SUL) carrier).

The first message (e.g., Msg 1 1311) may comprise one or more preambletransmissions (e.g., a preamble transmission and one or more preambleretransmissions). An RRC message may be used to configure one or morepreamble groups (e.g., group A and/or group B). A preamble group maycomprise one or more preambles. The wireless device may determine thepreamble group, for example, based on a pathloss measurement and/or asize of the third message (e.g., Msg 3 1313). The wireless device maymeasure an RSRP of one or more reference signals (e.g., SSBs and/orCSI-RSs) and determine at least one reference signal having an RSRPabove an RSRP threshold (e.g., rsrp-ThresholdSSB and/orrsrp-ThresholdCSl-RS). The wireless device may select at least onepreamble associated with the one or more reference signals and/or aselected preamble group, for example, if the association between the oneor more preambles and the at least one reference signal is configured byan RRC message.

The wireless device may determine the preamble, for example, based onthe one or more RACH parameters provided/configured/comprised in theconfiguration message 1310. The wireless device may determine thepreamble, for example, based on a pathloss measurement, an RSRPmeasurement, and/or a size of the third message (e.g., Msg 3 1313). Theone or more RACH parameters may indicate: a preamble format; a maximumquantity/number of preamble transmissions; and/or one or more thresholdsfor determining one or more preamble groups (e.g., group A and group B).A base station may use the one or more RACH parameters to configure thewireless device with an association between one or more preambles andone or more reference signals (e.g., SSBs and/or CSI-RSs). The wirelessdevice may determine the preamble to be comprised in first message(e.g., Msg 1 1311), for example, based on the association if theassociation is configured. The first message (e.g., Msg 1 1311) may besent/transmitted to the base station via one or more PRACH occasions.The wireless device may use one or more reference signals (e.g., SSBsand/or CSI-RSs) for selection of the preamble and for determining of thePRACH occasion. One or more RACH parameters (e.g.,ra-ssb-OccasionMskIndex and/or ra-OccasionList) may indicate anassociation between the PRACH occasions and the one or more referencesignals.

The wireless device may perform a preamble retransmission, for example,if no response is received after or in response to a preambletransmission (e.g., for a period of time, such as a monitoring windowfor monitoring an RAR). The wireless device may increase an uplinktransmit power for the preamble retransmission. The wireless device mayselect an initial preamble transmit power, for example, based on apathloss measurement and/or a target received preamble power configuredby the network. The wireless device may determine to resend/retransmit apreamble and may ramp up the uplink transmit power. The wireless devicemay receive one or more RACH parameters (e.g.,PREAMBLE_POWER_RAMPING_STEP) indicating a ramping step for the preambleretransmission. The ramping step may be an amount of incrementalincrease in uplink transmit power for a retransmission. The wirelessdevice may ramp up the uplink transmit power, for example, if thewireless device determines a reference signal (e.g., SSB and/or CSI-RS)that is the same as a previous preamble transmission. The wirelessdevice may count the quantity/number of preamble transmissions and/orretransmissions, for example, using a counter parameter (e.g.,PREAMBLE_TRANSMISSION_COUNTER). The wireless device may determine that arandom access procedure has been completed unsuccessfully, for example,if the quantity/number of preamble transmissions exceeds a thresholdconfigured by the one or more RACH parameters (e.g., preambleTransMax)without receiving a successful response (e.g., an RAR).

The second message (e.g., Msg 2 1312) (e.g., received by the wirelessdevice) may comprise an RAR. The second message (e.g., Msg 2 1312) maycomprise multiple RARs corresponding to multiple wireless devices. Thesecond message (e.g., Msg 2 1312) may be received, for example, after orin response to the transmitting of the first message (e.g., Msg 1 1311).The second message (e.g., Msg 2 1312) may be scheduled on the DL-SCH andmay be indicated by a PDCCH, for example, using a random access radionetwork temporary identifier (RA RNTI). The second message (e.g., Msg 21312) may indicate that the first message (e.g., Msg 1 1311) wasreceived by the base station. The second message (e.g., Msg 2 1312) maycomprise a time-alignment command that may be used by the wirelessdevice to adjust the transmission timing of the wireless device, ascheduling grant for transmission of the third message (e.g., Msg 31313), and/or a Temporary Cell RNTI (TC-RNTI). The wireless device maydetermine/start a time window (e.g., ra-ResponseWindow) to monitor aPDCCH for the second message (e.g., Msg 2 1312), for example, aftertransmitting the first message (e.g., Msg 1 1311) (e.g., a preamble).The wireless device may determine the start time of the time window, forexample, based on a PRACH occasion that the wireless device uses tosend/transmit the first message (e.g., Msg 1 1311) (e.g., the preamble).The wireless device may start the time window one or more symbols afterthe last symbol of the first message (e.g., Msg 1 1311) comprising thepreamble (e.g., the symbol in which the first message (e.g., Msg 1 1311)comprising the preamble transmission was completed or at a first PDCCHoccasion from an end of a preamble transmission). The one or moresymbols may be determined based on a numerology. The PDCCH may be mappedin a common search space (e.g., a Type1-PDCCH common search space)configured by an RRC message. The wireless device may identify/determinethe RAR, for example, based on an RNTI. Radio network temporaryidentifiers (RNTIs) may be used depending on one or more eventsinitiating/starting the random access procedure. The wireless device mayuse a RA-RNTI, for example, for one or more communications associatedwith random access or any other purpose. The RA-RNTI may be associatedwith PRACH occasions in which the wireless device sends/transmits apreamble. The wireless device may determine the RA-RNTI, for example,based on at least one of: an OFDM symbol index; a slot index; afrequency domain index; and/or a UL carrier indicator of the PRACHoccasions. An example RA-RNTI may be determined as follows:

RA-RNTI=1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id

where s_id may be an index of a first OFDM symbol of the PRACH occasion(e.g., 0≤s_id<14), t_id may be an index of a first slot of the PRACHoccasion in a system frame (e.g., 0≤t_id<80), f_id may be an index ofthe PRACH occasion in the frequency domain (e.g., 0≤f_id<8), andul_carrier_id may be a UL carrier used for a preamble transmission(e.g., 0 for an NUL carrier, and 1 for an SUL carrier).

The wireless device may send/transmit the third message (e.g., Msg 31313), for example, after or in response to a successful reception ofthe second message (e.g., Msg 2 1312) (e.g., using resources identifiedin the Msg 2 1312). The third message (e.g., Msg 3 1313) may be used,for example, for contention resolution in the contention-based randomaccess procedure. A plurality of wireless devices may send/transmit thesame preamble to a base station, and the base station may send/transmitan RAR that corresponds to a wireless device. Collisions may occur, forexample, if the plurality of wireless device interpret the RAR ascorresponding to themselves. Contention resolution (e.g., using thethird message (e.g., Msg 3 1313) and the fourth message (e.g., Msg 41314)) may be used to increase the likelihood that the wireless devicedoes not incorrectly use an identity of another the wireless device. Thewireless device may comprise a device identifier in the third message(e.g., Msg 3 1313) (e.g., a C-RNTI if assigned, a TC RNTI comprised inthe second message (e.g., Msg 2 1312), and/or any other suitableidentifier), for example, to perform contention resolution.

The fourth message (e.g., Msg 4 1314) may be received, for example,after or in response to the transmitting of the third message (e.g., Msg3 1313). The base station may address the wireless on the PDCCH (e.g.,the base station may send the PDCCH to the wireless device) using aC-RNTI, for example, If the C-RNTI was included in the third message(e.g., Msg 3 1313). The random access procedure may be determined to besuccessfully completed, for example, if the unique C RNTI of thewireless device is detected on the PDCCH (e.g., the PDCCH is scrambledby the C-RNTI). A fourth message (e.g., Msg 4 1314) may be receivedusing a DL-SCH associated with a TC RNTI, for example, if the TC RNTI iscomprised in the third message (e.g., Msg 3 1313) (e.g., if the wirelessdevice is in an RRC idle (e.g., an RRC_IDLE) state or not otherwiseconnected to the base station). The wireless device may determine thatthe contention resolution is successful and/or the wireless device maydetermine that the random access procedure is successfully completed,for example, if a MAC PDU is successfully decoded and a MAC PDUcomprises the wireless device contention resolution identity MAC CE thatmatches or otherwise corresponds with the CCCH SDU sent/transmitted inthird message (e.g., Msg 3 1313).

The wireless device may be configured with an SUL carrier and/or an NULcarrier. An initial access (e.g., random access) may be supported via anuplink carrier. A base station may configure the wireless device withmultiple RACH configurations (e.g., two separate RACH configurationscomprising: one for an SUL carrier and the other for an NUL carrier).For random access in a cell configured with an SUL carrier, the networkmay indicate which carrier to use (NUL or SUL). The wireless device maydetermine to use the SUL carrier, for example, if a measured quality ofone or more reference signals (e.g., one or more reference signalsassociated with the NUL carrier) is lower than a broadcast threshold.Uplink transmissions of the random access procedure (e.g., the firstmessage (e.g., Msg 1 1311) and/or the third message (e.g., Msg 3 1313))may remain on, or may be performed via, the selected carrier. Thewireless device may switch an uplink carrier during the random accessprocedure (e.g., between the Msg 1 1311 and the Msg 3 1313). Thewireless device may determine and/or switch an uplink carrier for thefirst message (e.g., Msg 1 1311) and/or the third message (e.g., Msg 31313), for example, based on a channel clear assessment (e.g., alisten-before-talk).

FIG. 13B shows a two-step random access procedure. The two-step randomaccess procedure may comprise a two-step contention-free random accessprocedure. Similar to the four-step contention-based random accessprocedure, a base station may, prior to initiation of the procedure,send/transmit a configuration message 1320 to the wireless device. Theconfiguration message 1320 may be analogous in some respects to theconfiguration message 1310. The procedure shown in FIG. 13B may comprisetransmissions of two messages: a first message (e.g., Msg 1 1321) and asecond message (e.g., Msg 2 1322). The first message (e.g., Msg 1 1321)and the second message (e.g., Msg 2 1322) may be analogous in somerespects to the first message (e.g., Msg 1 1311) and a second message(e.g., Msg 2 1312), respectively. The two-step contention-free randomaccess procedure may not comprise messages analogous to the thirdmessage (e.g., Msg 3 1313) and/or the fourth message (e.g., Msg 4 1314).

The two-step (e.g., contention-free) random access procedure may beconfigured/initiated for a beam failure recovery, other SI request, anSCell addition, and/or a handover. A base station may indicate, orassign to, the wireless device a preamble to be used for the firstmessage (e.g., Msg 1 1321). The wireless device may receive, from thebase station via a PDCCH and/or an RRC, an indication of the preamble(e.g., ra-Preamblelndex).

The wireless device may start a time window (e.g., ra-ResponseWindow) tomonitor a PDCCH for the RAR, for example, after or in response tosending/transmitting the preamble. The base station may configure thewireless device with one or more beam failure recovery parameters, suchas a separate time window and/or a separate PDCCH in a search spaceindicated by an RRC message (e.g., recoverySearchSpaceld). The basestation may configure the one or more beam failure recovery parameters,for example, in association with a beam failure recovery request. Theseparate time window for monitoring the PDCCH and/or an RAR may beconfigured to start after transmitting a beam failure recovery request(e.g., the window may start any quantity of symbols and/or slots aftertransmitting the beam failure recovery request). The wireless device maymonitor for a PDCCH transmission addressed to a Cell RNTI (C-RNTI) onthe search space. During the two-step (e.g., contention-free) randomaccess procedure, the wireless device may determine that a random accessprocedure is successful, for example, after or in response totransmitting first message (e.g., Msg 1 1321) and receiving acorresponding second message (e.g., Msg 2 1322). The wireless device maydetermine that a random access procedure has successfully beencompleted, for example, if a PDCCH transmission is addressed to acorresponding C-RNTI. The wireless device may determine that a randomaccess procedure has successfully been completed, for example, if thewireless device receives an RAR comprising a preamble identifiercorresponding to a preamble sent/transmitted by the wireless deviceand/or the RAR comprises a MAC sub-PDU with the preamble identifier. Thewireless device may determine the response as an indication of anacknowledgement for an SI request.

FIG. 13C shows an example two-step random access procedure. Similar tothe random access procedures shown in FIGS. 13A and 13B, a base stationmay, prior to initiation of the procedure, send/transmit a configurationmessage 1330 to the wireless device. The configuration message 1330 maybe analogous in some respects to the configuration message 1310 and/orthe configuration message 1320. The procedure shown in FIG. 13C maycomprise transmissions of multiple messages (e.g., two messagescomprising: a first message (e.g., Msg A 1331) and a second message(e.g., Msg B 1332)).

Msg A 1320 may be sent/transmitted in an uplink transmission by thewireless device. Msg A 1320 may comprise one or more transmissions of apreamble 1341 and/or one or more transmissions of a transport block1342. The transport block 1342 may comprise contents that are similarand/or equivalent to the contents of the third message (e.g., Msg 31313) (e.g., shown in FIG. 13A). The transport block 1342 may compriseUCI (e.g., an SR, a HARQ ACK/NACK, and/or the like). The wireless devicemay receive the second message (e.g., Msg B 1332), for example, after orin response to transmitting the first message (e.g., Msg A 1331). Thesecond message (e.g., Msg B 1332) may comprise contents that are similarand/or equivalent to the contents of the second message (e.g., Msg 21312) (e.g., an RAR shown in FIGS. 13A), the contents of the secondmessage (e.g., Msg 2 1322) (e.g., an RAR shown in FIG. 13B) and/or thefourth message (e.g., Msg 4 1314) (e.g., shown in FIG. 13A).

The wireless device may start/initiate the two-step random accessprocedure (e.g., the two-step random access procedure shown in FIG. 13C)for a licensed spectrum and/or an unlicensed spectrum. The wirelessdevice may determine, based on one or more factors, whether tostart/initiate the two-step random access procedure. The one or morefactors may comprise at least one of: a radio access technology in use(e.g., LTE, NR, and/or the like); whether the wireless device has avalid TA or not; a cell size; the RRC state of the wireless device; atype of spectrum (e.g., licensed vs. unlicensed); and/or any othersuitable factors.

The wireless device may determine, based on two-step RACH parameterscomprised in the configuration message 1330, a radio resource and/or anuplink transmit power for the preamble 1341 and/or the transport block1342 (e.g., comprised in the first message (e.g., Msg A 1331)). The RACHparameters may indicate an MCS, a time-frequency resource, and/or apower control for the preamble 1341 and/or the transport block 1342. Atime-frequency resource for transmission of the preamble 1341 (e.g., aPRACH) and a time-frequency resource for transmission of the transportblock 1342 (e.g., a PUSCH) may be multiplexed using FDM, TDM, and/orCDM. The RACH parameters may enable the wireless device to determine areception timing and a downlink channel for monitoring for and/orreceiving second message (e.g., Msg B 1332).

The transport block 1342 may comprise data (e.g., delay-sensitive data),an identifier of the wireless device, security information, and/ordevice information (e.g., an International Mobile Subscriber Identity(IMSI)). The base station may send/transmit the second message (e.g.,Msg B 1332) as a response to the first message (e.g., Msg A 1331). Thesecond message (e.g., Msg B 1332) may comprise at least one of: apreamble identifier; a timing advance command; a power control command;an uplink grant (e.g., a radio resource assignment and/or an MCS); awireless device identifier (e.g., a UE identifier for contentionresolution); and/or an RNTI (e.g., a C-RNTI or a TC-RNTI). The wirelessdevice may determine that the two-step random access procedure issuccessfully completed, for example, if a preamble identifier in thesecond message (e.g., Msg B 1332) corresponds to, or is matched to, apreamble sent/transmitted by the wireless device and/or the identifierof the wireless device in second message (e.g., Msg B 1332) correspondsto, or is matched to, the identifier of the wireless device in the firstmessage (e.g., Msg A 1331) (e.g., the transport block 1342).

A wireless device and a base station may exchange control signaling(e.g., control information).

The control signaling may be referred to as L1/L2 control signaling andmay originate from the PHY layer (e.g., layer 1) and/or the MAC layer(e.g., layer 2) of the wireless device or the base station. The controlsignaling may comprise downlink control signaling sent/transmitted fromthe base station to the wireless device and/or uplink control signalingsent/transmitted from the wireless device to the base station.

The downlink control signaling may comprise at least one of: a downlinkscheduling assignment; an uplink scheduling grant indicating uplinkradio resources and/or a transport format; slot format information; apreemption indication; a power control command; and/or any othersuitable signaling. The wireless device may receive the downlink controlsignaling in a payload sent/transmitted by the base station via a PDCCH.The payload sent/transmitted via the PDCCH may be referred to asdownlink control information (DCI). The PDCCH may be a group commonPDCCH (GC-PDCCH) that is common to a group of wireless devices. TheGC-PDCCH may be scrambled by a group common RNTI.

A base station may attach one or more cyclic redundancy check (CRC)parity bits to DCI, for example, in order to facilitate detection oftransmission errors. The base station may scramble the CRC parity bitswith an identifier of a wireless device (or an identifier of a group ofwireless devices), for example, if the DCI is intended for the wirelessdevice (or the group of the wireless devices). Scrambling the CRC paritybits with the identifier may comprise Modulo-2 addition (or anexclusive-OR operation) of the identifier value and the CRC parity bits.The identifier may comprise a 16-bit value of an RNTI.

DCIs may be used for different purposes. A purpose may be indicated bythe type of an RNTI used to scramble the CRC parity bits. DCI having CRCparity bits scrambled with a paging RNTI (P-RNTI) may indicate paginginformation and/or a system information change notification. The P-RNTImay be predefined as “FFFE” in hexadecimal. DCI having CRC parity bitsscrambled with a system information RNTI (SI-RNTI) may indicate abroadcast transmission of the system information. The SI-RNTI may bepredefined as “FFFF” in hexadecimal. DCI having CRC parity bitsscrambled with a random access RNTI (RA-RNTI) may indicate a randomaccess response (RAR). DCI having CRC parity bits scrambled with a cellRNTI (C-RNTI) may indicate a dynamically scheduled unicast transmissionand/or a triggering of PDCCH-ordered random access. DCI having CRCparity bits scrambled with a temporary cell RNTI (TC-RNTI) may indicatea contention resolution (e.g., a Msg 3 analogous to the Msg 3 1313 shownin FIG. 13A). Other RNTIs configured for a wireless device by a basestation may comprise a Configured Scheduling RNTI (CS RNTI), a TransmitPower Control-PUCCH RNTI (TPC PUCCH-RNTI), a Transmit PowerControl-PUSCH RNTI (TPC-PUSCH-RNTI), a Transmit Power Control-SRS RNTI(TPC-SRS-RNTI), an Interruption RNTI (INT-RNTI), a Slot FormatIndication RNTI (SFI-RNTI), a Semi-Persistent CSI RNTI (SP-CSI-RNTI), aModulation and Coding Scheme Cell RNTI (MCS-C RNTI), and/or the like.

A base station may send/transmit DCIs with one or more DCI formats, forexample, depending on the purpose and/or content of the DCIs. DCI format0_0 may be used for scheduling of a PUSCH in a cell. DCI format 0_0 maybe a fallback DCI format (e.g., with compact DCI payloads). DCI format0_1 may be used for scheduling of a PUSCH in a cell (e.g., with more DCIpayloads than DCI format 0_0). DCI format 1_0 may be used for schedulingof a PDSCH in a cell. DCI format 1_0 may be a fallback DCI format (e.g.,with compact DCI payloads). DCI format 1_1 may be used for scheduling ofa PDSCH in a cell (e.g., with more DCI payloads than DCI format 1_0).DCI format 2_0 may be used for providing a slot format indication to agroup of wireless devices. DCI format 2_1 may be used forinforming/notifying a group of wireless devices of a physical resourceblock and/or an OFDM symbol where the group of wireless devices mayassume no transmission is intended to the group of wireless devices. DCIformat 2_2 may be used for transmission of a transmit power control(TPC) command for PUCCH or PUSCH. DCI format 2_3 may be used fortransmission of a group of TPC commands for SRS transmissions by one ormore wireless devices. DCI format(s) for new functions may be defined infuture releases. DCI formats may have different DCI sizes, or may sharethe same DCI size.

The base station may process the DCI with channel coding (e.g., polarcoding), rate matching, scrambling and/or QPSK modulation, for example,after scrambling the DCI with an RNTI. A base station may map the codedand modulated DCI on resource elements used and/or configured for aPDCCH. The base station may send/transmit the DCI via a PDCCH occupyinga number of contiguous control channel elements (CCEs), for example,based on a payload size of the DCI and/or a coverage of the basestation. The number of the contiguous CCEs (referred to as aggregationlevel) may be 1, 2, 4, 8, 16, and/or any other suitable number. A CCEmay comprise a number (e.g., 6) of resource-element groups (REGs). A REGmay comprise a resource block in an OFDM symbol. The mapping of thecoded and modulated DCI on the resource elements may be based on mappingof CCEs and REGs (e.g., CCE-to-REG mapping).

FIG. 14A shows an example of CORESET configurations. The CORESETconfigurations may be for a bandwidth part or any other frequency bands.The base station may send/transmit DCI via a PDCCH on one or morecontrol resource sets (CORESETs). A CORESET may comprise atime-frequency resource in which the wireless device attempts/tries todecode DCI using one or more search spaces. The base station mayconfigure a size and a location of the CORESET in the time-frequencydomain. A first CORESET 1401 and a second CORESET 1402 may occur or maybe set/configured at the first symbol in a slot. The first CORESET 1401may overlap with the second CORESET 1402 in the frequency domain. Athird CORESET 1403 may occur or may be set/configured at a third symbolin the slot. A fourth CORESET 1404 may occur or may be set/configured atthe seventh symbol in the slot. CORESETs may have a different number ofresource blocks in frequency domain.

FIG. 14B shows an example of a CCE-to-REG mapping. The CCE-to-REGmapping may be performed for DCI transmission via a CORESET and PDCCHprocessing. The CCE-to-REG mapping may be an interleaved mapping (e.g.,for the purpose of providing frequency diversity) or a non-interleavedmapping (e.g., for the purposes of facilitating interferencecoordination and/or frequency-selective transmission of controlchannels). The base station may perform different or same CCE-to-REGmapping on different CORESETs. A CORESET may be associated with aCCE-to-REG mapping (e.g., by an RRC configuration). A CORESET may beconfigured with an antenna port QCL parameter. The antenna port QCLparameter may indicate QCL information of a DM-RS for a PDCCH receptionvia the CORESET.

The base station may send/transmit, to the wireless device, one or moreRRC messages comprising configuration parameters of one or more CORESETsand one or more search space sets. The configuration parameters mayindicate an association between a search space set and a CORESET. Asearch space set may comprise a set of PDCCH candidates formed by CCEs(e.g., at a given aggregation level). The configuration parameters mayindicate at least one of: a number of PDCCH candidates to be monitoredper aggregation level; a PDCCH monitoring periodicity and a PDCCHmonitoring pattern; one or more DCI formats to be monitored by thewireless device; and/or whether a search space set is a common searchspace set or a wireless device-specific search space set (e.g., aUE-specific search space set). A set of CCEs in the common search spaceset may be predefined and known to the wireless device. A set of CCEs inthe wireless device-specific search space set (e.g., the UE-specificsearch space set) may be configured, for example, based on the identityof the wireless device (e.g., C-RNTI).

As shown in FIG. 14B, the wireless device may determine a time-frequencyresource for a CORESET based on one or more RRC messages. The wirelessdevice may determine a CCE-to-REG mapping (e.g., interleaved ornon-interleaved, and/or mapping parameters) for the CORESET, forexample, based on configuration parameters of the CORESET. The wirelessdevice may determine a number (e.g., at most 10) of search space setsconfigured on/for the CORESET, for example, based on the one or more RRCmessages. The wireless device may monitor a set of PDCCH candidatesaccording to configuration parameters of a search space set. Thewireless device may monitor a set of PDCCH candidates in one or moreCORESETs for detecting one or more DCIs. Monitoring may comprisedecoding one or more PDCCH candidates of the set of the PDCCH candidatesaccording to the monitored DCI formats. Monitoring may comprise decodingDCI content of one or more PDCCH candidates with possible (orconfigured) PDCCH locations, possible (or configured) PDCCH formats(e.g., the number of CCEs, the number of PDCCH candidates in commonsearch spaces, and/or the number of PDCCH candidates in the wirelessdevice-specific search spaces) and possible (or configured) DCI formats.The decoding may be referred to as blind decoding. The wireless devicemay determine DCI as valid for the wireless device, for example, afteror in response to CRC checking (e.g., scrambled bits for CRC parity bitsof the DCI matching an RNTI value). The wireless device may processinformation comprised in the DCI (e.g., a scheduling assignment, anuplink grant, power control, a slot format indication, a downlinkpreemption, and/or the like).

The wireless device may send/transmit uplink control signaling (e.g.,UCI) to a base station. The uplink control signaling may comprise HARQacknowledgements for received DL-SCH transport blocks. The wirelessdevice may send/transmit the HARQ acknowledgements, for example, afteror in response to receiving a DL-SCH transport block. Uplink controlsignaling may comprise CSI indicating a channel quality of a physicaldownlink channel. The wireless device may send/transmit the CSI to thebase station. The base station, based on the received CSI, may determinetransmission format parameters (e.g., comprising multi-antenna andbeamforming schemes) for downlink transmission(s). Uplink controlsignaling may comprise scheduling requests (SR). The wireless device maysend/transmit an SR indicating that uplink data is available fortransmission to the base station. The wireless device may send/transmitUCI (e.g., HARQ acknowledgements (HARQ-ACK), CSI report, SR, and thelike) via a PUCCH or a PUSCH. The wireless device may send/transmit theuplink control signaling via a PUCCH using one of several PUCCH formats.

There may be multiple PUCCH formats (e.g., five PUCCH formats). Awireless device may determine a PUCCH format, for example, based on asize of UCI (e.g., a quantity/number of uplink symbols of UCItransmission and a number of UCI bits). PUCCH format 0 may have a lengthof one or two OFDM symbols and may comprise two or fewer bits. Thewireless device may send/transmit UCI via a PUCCH resource, for example,using PUCCH format 0 if the transmission is over/via one or two symbolsand the quantity/number of HARQ-ACK information bits with positive ornegative SR (HARQ-ACK/SR bits) is one or two. PUCCH format 1 may occupya number of OFDM symbols (e.g., between four and fourteen OFDM symbols)and may comprise two or fewer bits. The wireless device may use PUCCHformat 1, for example, if the transmission is over/via four or moresymbols and the number of HARQ-ACK/SR bits is one or two. PUCCH format 2may occupy one or two OFDM symbols and may comprise more than two bits.The wireless device may use PUCCH format 2, for example, if thetransmission is over/via one or two symbols and the quantity/number ofUCI bits is two or more. PUCCH format 3 may occupy a number of OFDMsymbols (e.g., between four and fourteen OFDM symbols) and may comprisemore than two bits. The wireless device may use PUCCH format 3, forexample, if the transmission is four or more symbols, thequantity/number of UCI bits is two or more, and the PUCCH resource doesnot comprise an orthogonal cover code (OCC). PUCCH format 4 may occupy anumber of OFDM symbols (e.g., between four and fourteen 01-DM symbols)and may comprise more than two bits. The wireless device may use PUCCHformat 4, for example, if the transmission is four or more symbols, thequantity/number of UCI bits is two or more, and the PUCCH resourcecomprises an OCC.

The base station may send/transmit configuration parameters to thewireless device for a plurality of PUCCH resource sets, for example,using an RRC message. The plurality of PUCCH resource sets (e.g., up tofour sets in NR, or up to any other quantity of sets in other systems)may be configured on an uplink BWP of a cell. A PUCCH resource set maybe configured with a PUCCH resource set index, a plurality of PUCCHresources with a PUCCH resource being identified by a PUCCH resourceidentifier (e.g., pucch-Resourceid), and/or a number (e.g. a maximumnumber) of UCI information bits the wireless device may send/transmitusing one of the plurality of PUCCH resources in the PUCCH resource set.The wireless device may select one of the plurality of PUCCH resourcesets, for example, based on a total bit length of the UCI informationbits (e.g., HARQ-ACK, SR, and/or CSI) if configured with a plurality ofPUCCH resource sets. The wireless device may select a first PUCCHresource set having a PUCCH resource set index equal to “0,” forexample, if the total bit length of UCI information bits is two orfewer. The wireless device may select a second PUCCH resource set havinga PUCCH resource set index equal to “1,” for example, if the total bitlength of UCI information bits is greater than two and less than orequal to a first configured value. The wireless device may select athird PUCCH resource set having a PUCCH resource set index equal to “2,”for example, if the total bit length of UCI information bits is greaterthan the first configured value and less than or equal to a secondconfigured value. The wireless device may select a fourth PUCCH resourceset having a PUCCH resource set index equal to “3,” for example, if thetotal bit length of UCI information bits is greater than the secondconfigured value and less than or equal to a third value (e.g., 1406,1706, or any other quantity of bits).

The wireless device may determine a PUCCH resource from the PUCCHresource set for UCI

(HARQ-ACK, CSI, and/or SR) transmission, for example, after determininga PUCCH resource set from a plurality of PUCCH resource sets. Thewireless device may determine the PUCCH resource, for example, based ona PUCCH resource indicator in DCI (e.g., with DCI format 1_0 or DCI for1_1) received on/via a PDCCH. An n-bit (e.g., a three-bit) PUCCHresource indicator in the DCI may indicate one of multiple (e.g., eight)PUCCH resources in the PUCCH resource set. The wireless device maysend/transmit the UCI (HARQ-ACK, CSI and/or SR) using a PUCCH resourceindicated by the PUCCH resource indicator in the DCI, for example, basedon the PUCCH resource indicator.

FIG. 15A shows an example communications between a wireless device and abase station. A wireless device 1502 and a base station 1504 may be partof a communication network, such as the communication network 100 shownin FIG. 1A, the communication network 150 shown in FIG. 1B, or any othercommunication network. A communication network may comprise more thanone wireless device and/or more than one base station, withsubstantially the same or similar configurations as those shown in FIG.15A.

The base station 1504 may connect the wireless device 1502 to a corenetwork (not shown) via radio communications over the air interface (orradio interface) 1506. The communication direction from the base station1504 to the wireless device 1502 over the air interface 1506 may bereferred to as the downlink. The communication direction from thewireless device 1502 to the base station 1504 over the air interface maybe referred to as the uplink. Downlink transmissions may be separatedfrom uplink transmissions, for example, using various duplex schemes(e.g., FDD, TDD, and/or some combination of the duplexing techniques).

For the downlink, data to be sent to the wireless device 1502 from thebase station 1504 may be provided/transferred/sent to the processingsystem 1508 of the base station 1504. The data may beprovided/transferred/sent to the processing system 1508 by, for example,a core network. For the uplink, data to be sent to the base station 1504from the wireless device 1502 may be provided/transferred/sent to theprocessing system 1518 of the wireless device 1502. The processingsystem 1508 and the processing system 1518 may implement layer 3 andlayer 2 OSI functionality to process the data for transmission. Layer 2may comprise an SDAP layer, a PDCP layer, an RLC layer, and a MAC layer,for example, described with respect to FIG. 2A, FIG. 2B, FIG. 3, andFIG. 4A. Layer 3 may comprise an RRC layer, for example, described withrespect to FIG. 2B.

The data to be sent to the wireless device 1502 may beprovided/transferred/sent to a transmission processing system 1510 ofbase station 1504, for example, after being processed by the processingsystem 1508. The data to be sent to base station 1504 may beprovided/transferred/sent to a transmission processing system 1520 ofthe wireless device 1502, for example, after being processed by theprocessing system 1518. The transmission processing system 1510 and thetransmission processing system 1520 may implement layer 1 OSIfunctionality. Layer 1 may comprise a PHY layer, for example, describedwith respect to FIG. 2A, FIG. 2B, FIG. 3, and FIG. 4A. For transmitprocessing, the PHY layer may perform, for example, forward errorcorrection coding of transport channels, interleaving, rate matching,mapping of transport channels to physical channels, modulation ofphysical channel, multiple-input multiple-output (MIMO) or multi-antennaprocessing, and/or the like.

A reception processing system 1512 of the base station 1504 may receivethe uplink transmission from the wireless device 1502. The receptionprocessing system 1512 of the base station 1504 may comprise one or moreTRPs. A reception processing system 1522 of the wireless device 1502 mayreceive the downlink transmission from the base station 1504. Thereception processing system 1522 of the wireless device 1502 maycomprise one or more antenna panels. The reception processing system1512 and the reception processing system 1522 may implement layer 1 OSIfunctionality. Layer 1 may include a PHY layer, for example, describedwith respect to FIG. 2A, FIG. 2B, FIG. 3, and FIG. 4A. For receiveprocessing, the PHY layer may perform, for example, error detection,forward error correction decoding, deinterleaving, demapping oftransport channels to physical channels, demodulation of physicalchannels, MIMO or multi-antenna processing, and/or the like.

The base station 1504 may comprise multiple antennas (e.g., multipleantenna panels, multiple TRPs, etc.). The wireless device 1502 maycomprise multiple antennas (e.g., multiple antenna panels, etc.). Themultiple antennas may be used to perform one or more MIMO ormulti-antenna techniques, such as spatial multiplexing (e.g.,single-user MIMO or multi-user MIMO), transmit/receive diversity, and/orbeamforming. The wireless device 1502 and/or the base station 1504 mayhave a single antenna.

The processing system 1508 and the processing system 1518 may beassociated with a memory 1514 and a memory 1524, respectively. Memory1514 and memory 1524 (e.g., one or more non-transitory computer readablemediums) may store computer program instructions or code that may beexecuted by the processing system 1508 and/or the processing system1518, respectively, to carry out one or more of the functionalities(e.g., one or more functionalities described herein and otherfunctionalities of general computers, processors, memories, and/or otherperipherals). The transmission processing system 1510 and/or thereception processing system 1512 may be coupled to the memory 1514and/or another memory (e.g., one or more non-transitory computerreadable mediums) storing computer program instructions or code that maybe executed to carry out one or more of their respectivefunctionalities. The transmission processing system 1520 and/or thereception processing system 1522 may be coupled to the memory 1524and/or another memory (e.g., one or more non-transitory computerreadable mediums) storing computer program instructions or code that maybe executed to carry out one or more of their respectivefunctionalities.

The processing system 1508 and/or the processing system 1518 maycomprise one or more controllers and/or one or more processors. The oneor more controllers and/or one or more processors may comprise, forexample, a general-purpose processor, a digital signal processor (DSP),a microcontroller, an application specific integrated circuit (ASIC), afield programmable gate array (FPGA) and/or other programmable logicdevice, discrete gate and/or transistor logic, discrete hardwarecomponents, an on-board unit, or any combination thereof. The processingsystem 1508 and/or the processing system 1518 may perform at least oneof signal coding/processing, data processing, power control,input/output processing, and/or any other functionality that may enablethe wireless device 1502 and/or the base station 1504 to operate in awireless environment.

The processing system 1508 may be connected to one or more peripherals1516. The processing system 1518 may be connected to one or moreperipherals 1526. The one or more peripherals 1516 and the one or moreperipherals 1526 may comprise software and/or hardware that providefeatures and/or functionalities, for example, a speaker, a microphone, akeypad, a display, a touchpad, a power source, a satellite transceiver,a universal serial bus (USB) port, a hands-free headset, a frequencymodulated (FM) radio unit, a media player, an Internet browser, anelectronic control unit (e.g., for a motor vehicle), and/or one or moresensors (e.g., an accelerometer, a gyroscope, a temperature sensor, aradar sensor, a lidar sensor, an ultrasonic sensor, a light sensor, acamera, and/or the like). The processing system 1508 and/or theprocessing system 1518 may receive input data (e.g., user input data)from, and/or provide output data (e.g., user output data) to, the one ormore peripherals 1516 and/or the one or more peripherals 1526. Theprocessing system 1518 in the wireless device 1502 may receive powerfrom a power source and/or may be configured to distribute the power tothe other components in the wireless device 1502. The power source maycomprise one or more sources of power, for example, a battery, a solarcell, a fuel cell, or any combination thereof. The processing system1508 may be connected to a Global Positioning System (GPS) chipset 1517.The processing system 1518 may be connected to a Global PositioningSystem (GPS) chipset 1527. The GPS chipset 1517 and the GPS chipset 1527may be configured to determine and provide geographic locationinformation of the wireless device 1502 and the base station 1504,respectively.

FIG. 15B shows example elements of a computing device that may be usedto implement any of the various devices described herein, including, forexample, the base station 160A, 160B, 162A, 162B, 220, and/or 1504, thewireless device 106, 156A, 156B, 210, and/or 1502, or any other basestation, wireless device, AMF, UPF, network device, or computing devicedescribed herein. The computing device 1530 may include one or moreprocessors 1531, which may execute instructions stored in therandom-access memory (RAM) 1533, the removable media 1534 (such as aUniversal Serial Bus (USB) drive, compact disk (CD) or digital versatiledisk (DVD), or floppy disk drive), or any other desired storage medium.Instructions may also be stored in an attached (or internal) hard drive1535. The computing device 1530 may also include a security processor(not shown), which may execute instructions of one or more computerprograms to monitor the processes executing on the processor 1531 andany process that requests access to any hardware and/or softwarecomponents of the computing device 1530 (e.g., ROM 1532, RAM 1533, theremovable media 1534, the hard drive 1535, the device controller 1537, anetwork interface 1539, a GPS 1541, a Bluetooth interface 1542, a WiFiinterface 1543, etc.). The computing device 1530 may include one or moreoutput devices, such as the display 1536 (e.g., a screen, a displaydevice, a monitor, a television, etc.), and may include one or moreoutput device controllers 1537, such as a video processor. There mayalso be one or more user input devices 1538, such as a remote control,keyboard, mouse, touch screen, microphone, etc. The computing device1530 may also include one or more network interfaces, such as a networkinterface 1539, which may be a wired interface, a wireless interface, ora combination of the two. The network interface 1539 may provide aninterface for the computing device 1530 to communicate with a network1540 (e.g., a RAN, or any other network). The network interface 1539 mayinclude a modem (e.g., a cable modem), and the external network 1540 mayinclude communication links, an external network, an in-home network, aprovider's wireless, coaxial, fiber, or hybrid fiber/coaxialdistribution system (e.g., a DOCSIS network), or any other desirednetwork. Additionally, the computing device 1530 may include alocation-detecting device, such as a global positioning system (GPS)microprocessor 1541, which may be configured to receive and processglobal positioning signals and determine, with possible assistance froman external server and antenna, a geographic position of the computingdevice 1530.

The example in FIG. 15B may be a hardware configuration, although thecomponents shown may be implemented as software as well. Modificationsmay be made to add, remove, combine, divide, etc. components of thecomputing device 1530 as desired. Additionally, the components may beimplemented using basic computing devices and components, and the samecomponents (e.g., processor 1531, ROM storage 1532, display 1536, etc.)may be used to implement any of the other computing devices andcomponents described herein. For example, the various componentsdescribed herein may be implemented using computing devices havingcomponents such as a processor executing computer-executableinstructions stored on a computer-readable medium, as shown in FIG. 15B.Some or all of the entities described herein may be software based, andmay co-exist in a common physical platform (e.g., a requesting entitymay be a separate software process and program from a dependent entity,both of which may be executed as software on a common computing device).

FIG. 16A shows an example structure for uplink transmission. Processingof a baseband signal representing a physical uplink shared channel maycomprise/perform one or more functions. The one or more functions maycomprise at least one of: scrambling; modulation of scrambled bits togenerate complex-valued symbols; mapping of the complex-valuedmodulation symbols onto one or several transmission layers; transformprecoding to generate complex-valued symbols; precoding of thecomplex-valued symbols; mapping of precoded complex-valued symbols toresource elements; generation of complex-valued time-domain SingleCarrier-Frequency Division Multiple Access (SC-FDMA), CP-OFDM signal foran antenna port, or any other signals; and/or the like. An SC-FDMAsignal for uplink transmission may be generated, for example, iftransform precoding is enabled. A CP-OFDM signal for uplink transmissionmay be generated, for example, if transform precoding is not enabled(e.g., as shown in FIG. 16A). These functions are examples and othermechanisms for uplink transmission may be implemented.

FIG. 16B shows an example structure for modulation and up-conversion ofa baseband signal to a carrier frequency. The baseband signal may be acomplex-valued SC-FDMA, CP-OFDM baseband signal (or any other basebandsignals) for an antenna port and/or a complex-valued Physical RandomAccess Channel (PRACH) baseband signal. Filtering may beperformed/employed, for example, prior to transmission.

FIG. 16C shows an example structure for downlink transmissions.Processing of a baseband signal representing a physical downlink channelmay comprise/perform one or more functions. The one or more functionsmay comprise: scrambling of coded bits in a codeword to besent/transmitted on/via a physical channel; modulation of scrambled bitsto generate complex-valued modulation symbols; mapping of thecomplex-valued modulation symbols onto one or several transmissionlayers; precoding of the complex-valued modulation symbols on a layerfor transmission on the antenna ports; mapping of complex-valuedmodulation symbols for an antenna port to resource elements; generationof complex-valued time-domain OFDM signal for an antenna port; and/orthe like. These functions are examples and other mechanisms for downlinktransmission may be implemented.

FIG. 16D shows an example structure for modulation and up-conversion ofa baseband signal to a carrier frequency. The baseband signal may be acomplex-valued OFDM baseband signal for an antenna port or any othersignal. Filtering may be performed/employed, for example, prior totransmission.

A wireless device may receive, from a base station, one or more messages(e.g. RRC messages) comprising configuration parameters of a pluralityof cells (e.g., a primary cell, one or more secondary cells). Thewireless device may communicate with at least one base station (e.g.,two or more base stations in dual-connectivity) via the plurality ofcells. The one or more messages (e.g. as a part of the configurationparameters) may comprise parameters of PHY, MAC, RLC, PCDP, SDAP, RRClayers for configuring the wireless device. The configuration parametersmay comprise parameters for configuring PHY and MAC layer channels,bearers, etc. The configuration parameters may comprise parametersindicating values of timers for PHY, MAC, RLC, PCDP, SDAP, RRC layers,and/or communication channels.

A timer may begin running, for example, if it is started and continuerunning until it is stopped or until it expires. A timer may be started,for example, if it is not running or restarted if it is running A timermay be associated with a value (e.g., the timer may be started orrestarted from a value or may be started from zero and expire if itreaches the value). The duration of a timer may not be updated, forexample, until the timer is stopped or expires (e.g., due to BWPswitching). A timer may be used to measure a time period/window for aprocess. With respect to an implementation and/or procedure related toone or more timers or other parameters, it will be understood that theremay be multiple ways to implement the one or more timers or otherparameters. One or more of the multiple ways to implement a timer may beused to measure a time period/window for the procedure. A random accessresponse window timer may be used for measuring a window of time forreceiving a random access response. The time difference between two timestamps may be used, for example, instead of starting a random accessresponse window timer and determine the expiration of the timer. Aprocess for measuring a time window may be restarted, for example, if atimer is restarted. Other example implementations may beconfigured/provided to restart a measurement of a time window.

FIG. 17 shows an example of wireless communications. There may be adirect communication between wireless devices, for example, in wirelesscommunication (e.g., sidelink communications, device-to-device (D2D)commuincations, vehicle-to-everything (V2X) communications, etc.). Thedirect communication may be performed via a communications link, such asa sidelink (SL) or any other link. The wireless devices may exchangecommunications, such as sidelink communications, via an interface suchas a sidelink interface (e.g., a PC5 interface). The directcommunications, such as sidelink communications, may differ from uplinkcommunications (e.g., in which a wireless device may communicate to abase station) and/or downlink communications (e.g., in which a basestation may communicate to a wireless device). Reference made herein tosidelink, SL, and/or to sidelink communications may comprise any linkand/or any link communications, including, for example, any direct linkand/or any direct link communications between any user devices (e.g.,wireless devices, user devices, user equipments, etc.). Althoughsidelink is used as an example, one skilled in the art will appreciatethat any communications can use these concepts. A wireless device and abase station may exchange uplink and/or downlink communications via aninterface, such as a user plane interface (e.g., a Uu interface).

A first wireless device (e.g., a wireless device 1701) and a secondwireless device (e.g., a wireless device 1702) may be in a firstcoverage area (e.g., a coverage area 1720) of a first base station(e.g., a base station 1710). The first wireless device and the secondwireless device may communicate with the first base station, forexample, via a Uu interface. The coverage area may comprise any quantityof wireless devices that may communicate with the base station. A thirdwireless device (e.g., a wireless device 1703) may be in a secondcoverage area (e.g., a coverage area 1721) of a second base station(e.g., a base station 1711). The second coverage area may comprise anyquantity of wireless devices that may communicate with the second basestation. The first base station and the second base station may share anetwork and/or may jointly establish/provide a network coverage area(e.g., 1720 and 1721). A fourth wireless device (e.g., a wireless device1704) and a fifth wireless device (e.g., a wireless device 1705) may beoutside of the network coverage area (e.g., 1720 and 1721). Any quantityof wireless devices that may be outside of the network coverage area(e.g., 1720 and 1721).

Wireless communications may comprise in-coverage D2D communication.In-coverage D2D communication may be performed, for example, if two ormore wireless devices share a network coverage area. The first wirelessdevice and the second wireless device may be in the first coverage areaof the first base station. The first wireless device and the secondwireless device may perform a direct communication (e.g., an in-coverageintra-cell direct communication via a sidelink 1724). The secondwireless device and the third wireless device may be in the coverageareas of different base stations (e.g., 1710 and 1711) and/or may sharethe same network coverage area (e.g., 1720 and/or 1721). The secondwireless device and the third wireless device may perform a directcommunication (e.g., an in-coverage inter-cell direct communication viaa sidelink 1725). Partial-coverage direct communications (e.g.,partial-coverage D2D communications, partial-coverage V2Xcommunications, partial-coverage sidelink communications, etc.) may beperformed. Partial-coverage direct communications may be performed, forexample, if one wireless device is within the network coverage area andthe other wireless device is outside the network coverage area. Thethird wireless device and the fourth wireless device may perform apartial-coverage direct communication (e.g., via a sidelink 1722).Out-of-coverage direct communications may be performed. Out-of-coveragedirect communications may be performed, for example, if both wirelessdevices are outside of a network coverage area. The fourth wirelessdevice and the fifth wireless device may perform an out-of-coveragedirect communication (e.g., via a sidelink 1723).

Wireless communications, such as sidelink communications, may beconfigured using physical channels. Wireless communications, such assidelink communications, may be configured using physical channels, forexample, a physical sidelink broadcast channel (PSBCH), a physicalsidelink feedback channel (PSFCH), a physical sidelink discovery channel(PSDCH), a physical sidelink control channel (PSCCH), and/or a physicalsidelink shared channel (PSSCH). PSBCH may be used by a first wirelessdevice to send broadcast information to a second wireless device. APSBCH may be similar in some respects to a PBCH. The broadcastinformation may comprise a slot format indication, resource poolinformation, a sidelink system frame number, and/or any other suitablebroadcast information. A PSFCH may be used by a first wireless device tosend feedback information to a second wireless device. The feedbackinformation may comprise HARQ feedback information. A PSDCH may be usedby a first wireless device to send discovery information to a secondwireless device. The discovery information may be used by a wirelessdevice to signal its presence and/or the availability of services toother wireless devices in the area. A PSCCH may be used by a firstwireless device to send sidelink control information (SCI) to a secondwireless device. A PSCCH may be similar in some respects to PDCCH and/orPUCCH. The control information may comprise time/frequency resourceallocation information (e.g., RB size, a number of retransmissions,etc.), demodulation related information (e.g., DM-RS, MCS, redundancyversion (RV), etc.), identifying information for a sending (e.g.,transmitting) wireless device and/or a receiving wireless device, aprocess identifier (e.g., HARQ, etc.), and/or any other suitable controlinformation. The PSCCH may be used to allocate, prioritize, and/orreserve sidelink resources for sidelink transmissions. PSSCH may be usedby a first wireless device to send and/or relay data and/or networkinformation to a second wireless device. PSSCH may be similar in somerespects to PDSCH and/or PUSCH. A sidelink channel may be associatedwith one or more demodulation reference signals. For example, each ofthe sidelink channels may be associated with one or more demodulationreference signals. Sidelink operations may utilize sidelinksynchronization signals to establish a timing of sidelink operations.Wireless devices configured for sidelink operations may send sidelinksynchronization signals, for example, with the PSBCH. The sidelinksynchronization signals may include primary sidelink synchronizationsignals (PSSS) and/or secondary sidelink synchronization signals (SSSS).

A wireless device may be configured with wireless resources (e.g.,sidelink resources). A wireless device may be configured (e.g.,pre-configured) for a sidelink. A wireless device may be configured(e.g., pre-configured) with sidelink resource information. A network maybroadcast system information relating to a resource pool for a sidelink.A network may configure a particular wireless device with a dedicatedsidelink configuration. The configuration may identify/indicate sidelinkresources to be used for sidelink operation (e.g., configure a sidelinkband combination).

A wireless device may operate in one or more (e.g., different) modes.The wireless device may operate in an assisted mode (e.g., mode 1)and/or an autonomous mode (e.g., mode 2). Mode selection may be based ona coverage status of the wireless device, a radio resource controlstatus of the wireless device, information and/or instructions from thenetwork, and/or any other suitable factors. The wireless device mayselect to operate in autonomous mode. The wireless device may select tooperate in autonomous mode, for example, if the wireless device is idleor inactive, or if the wireless device is outside of network coverage.The wireless device may select to operate (or be instructed by a basestation to operate) in an assisted mode. The wireless device may selectto operate (or be instructed by a base station to operate) in anassisted mode, for example, if the wireless device is in a connectedmode (e.g., connected to a base station). The network (e.g., a basestation) may instruct a connected wireless device to operate in aparticular mode.

The wireless device may request scheduling from the network. Thewireless device may request scheduling from the network, for example, inan assisted mode. The wireless device may send a scheduling request tothe network and the network may allocate sidelink resources to thewireless device. Assisted mode may be referred to as network-assistedmode, gNB-assisted mode, or a base station-assisted mode. The wirelessdevice may select sidelink resources. The wireless device may selectsidelink resources, for example, in an autonomous mode. The wirelessdevice may select sidelink resources, for example, based on measurementswithin one or more resource pools (e.g., pre-configured resource pools,network-assigned resource pools), sidelink resource selections made byother wireless devices, and/or sidelink resource usage of other wirelessdevices.

A wireless device may use a sensing window. A wireless device may use aselection window. A wireless device may use a sensing window and/or aselection window, for example, to determine/select sidelink resources.The wireless device may receive/determine SCI sent (e.g., transmitted)by other wireless devices using a sidelink resource pool. The wirelessdevice may receive/determine SCI sent (e.g., transmitted) by otherwireless devices using the sidelink resource pool, for example, in thesensing window. The SCIs may identify/determine resources that may beused and/or reserved for sidelink transmissions. The wireless device maydetermine/select resources within the selection window (e.g., resourcesthat are different from the resources identified in the SCIs). Thewireless device may determine/select resources within the selectionwindow, for example, based on the resources identified in the SCIs. Thewireless device may send (e.g., transmit) using the selected sidelinkresources.

FIG. 18 shows an example of a resource pool for sidelink operations. Awireless device may operate using one or more sidelink cells. A sidelinkcell may include one or more resource pools. A resource pool (e.g., eachresource pool) may be configured to operate in accordance with aparticular mode (e.g., assisted mode, autonomous mode, and/or any othermode). The resource pool may be divided into one or more resource units(e.g., one or more resources). Each resource unit may comprise one ormore resource blocks. Each resource unit may comprise one or moreresource blocks, for example, in the frequency domain. Each resourceunit may comprise one or more resource blocks, for example, which may bereferred to as a sub-channel. Each resource unit may comprise one ormore slots, one or more subframes, and/or one or more OFDM symbols. Eachresource unit may comprise one or more slots, one or more subframes,and/or one or more OFDM symbols, for example, in the time domain. Theresource pool may be continuous or non-continuous in the frequencydomain and/or the time domain (e.g., comprising contiguous resourceunits or non-contiguous resource units). The resource pool may bedivided into repeating resource pool portions. The resource pool may beshared among one or more wireless devices. Each wireless device mayattempt to send (e.g., transmit) using different resource units, forexample, to avoid collisions.

A resource pool (e.g., a sidelink resource pool) may be arranged in anysuitable manner. The resource pool may be non-contiguous in the timedomain and/or confined to a single sidelink BWP, for example, as shownin FIG. 18. Frequency resources may be divided into Nf resource unitsper unit of time, for example, as shown in FIG. 18. Frequency resourcesmay be numbered from zero to Nf-1, for example, as shown in FIG. 18. Theexample resource pool may comprise a plurality of portions (e.g.,non-contiguous portions) that may repeat every k units of time. Timeresources may be numbered as n, n+1 . . . n+k, n+k+1 . . . , etc., forexample, as shown in FIG. 18.

A wireless device may determine/select for transmission one or moreresource units from a resource pool. The wireless device may selectresource unit (n,0) for sidelink transmission. The wireless device maydetermine/select periodic resource units in later portions of theresource pool, for example, resource unit (n+k,0), resource unit(n+2k,0), resource unit (n+3k,0), etc. The wireless device maydetermine/select periodic resource units, for example, based on adetermination that a transmission using resource unit (n,0) will not (oris not likely) to collide with a sidelink transmission of a wirelessdevice that shares the sidelink resource pool. The determination may bebased on behavior of other wireless devices that share the resourcepool. The wireless device may select resource unit (n,0), resource(n+k,0), etc., for example, if no sidelink transmissions are detected inresource unit (n-k,0). The wireless device may avoid selection ofresource unit (n,1), resource (n+k,1), etc., for example, if a sidelinktransmission from another wireless device is detected in resource unit(n−k,1).

Different sidelink physical channels may use different resource pools.PSCCH may use a first resource pool and PSSCH may use a second resourcepool. Different resource priorities may be associated with differentresource pools. Data associated with a first QoS, service, priority,and/or other characteristic may use a first resource pool and dataassociated with a second QoS, service, priority, and/or othercharacteristic may use a second resource pool. A network (e.g., a basestation) may configure a priority level for each resource pool, aservice to be supported for each resource pool, etc. A network (e.g., abase station) may configure a first resource pool for use by unicastwireless devices (e.g., UEs), a second resource pool for use bygroupcast wireless devices (e.g., UEs), etc. A network (e.g., a basestation) may configure a first resource pool for transmission ofsidelink data, a second resource pool for transmission of discoverymessages, etc.

FIG. 19 shows an example of timing for a resource selection procedure. Awireless device may perform the resource selection procedure to selectradio resources for a sidelink transmission. A sensing window 1901 ofthe resource selection procedure may start at time (n−T0), for example,as shown in FIG. 19. The sensing window 1901 may end at time(n−T_(proc,0)). The wireless device may receive new data for thesidelink transmission at time (n−T_(proc,0)). The time period T_(proc,0)may be a processing delay of the wireless device to determine to triggerthe resource selection procedure. The wireless device may determine totrigger the resource selection procedure at time n to select the radioresources for the new data arrived at time (n−T_(proc,0)). The wirelessdevice may complete the resource selection procedure at time (n+T1). Thewireless device may determine the parameter T1, for example, based on acapability of the wireless device. The capability of the wireless devicemay be based on a processing delay of a processor of the wirelessdevice. A selection window 1902 of the resource selection procedure maystart at time (n+T1). The selection window 1902 may end at time (n+T2).The time (n+T2) may indicate/define the ending of the selection window.The wireless device may determine the parameter T2 subject toT2min≤T2≤PDB, for example, where the PDB (packet delay budget) may be anallowable delay, such as a maximum allowable delay, (e.g., a delaybudget) for sending (e.g., transmitting) the new data via the sidelinktransmission. The wireless device may determine/set the parameter T2minto a corresponding value for a priority of the sidelink transmission.The wireless device may determine/set the parameter T2=PDB, for example,if the parameter T2min>PDB.

FIG. 20 shows an example of a resource indication. The resourceindication may comprise a resource indication for a first TB and/or aresource reservation for a second TB. A sidelink transmission maycomprise an SCI. The sidelink transmission may comprise a TB. The SCImay comprise one or more first parameters indicating one or more firsttime and frequency (T/F) resources for transmission and/orretransmission of the first TB. The SCI may comprise one or more secondparameters indicating a reservation period of one or more second T/Fresources for transmission and/or retransmission of the second TB.

A wireless device may determine/select one or more first T/F resourcesfor transmission and/or retransmission of a first TB. A wireless devicemay determine/select one or more first T/F resources for transmissionand/or retransmission of the first TB, for example, based on triggeringa resource selection procedure (e.g., as described above in FIG. 19).The wireless device may select three resources for sending (e.g.,transmitting) the first TB, for example, such as shown in FIG. 20. Thewireless device may send (e.g., transmit) an initial transmission (e.g.,an initial Tx of a first TB in FIG. 20) of the first TB via a firstresource 2001 of the three resources. The wireless device may send(e.g., transmit) a first retransmission (e.g., a 1st re-Tx in FIG. 20)of the first TB via a second resource 2011 of the three resources. Thewireless device may send (e.g., transmit) a second retransmission (e.g.,a 2nd re-Tx in FIG. 20) of the first TB via a third resource 2021 of thethree resources. A time duration between a starting time of the initialtransmission of the first TB (e.g., via the first resource 2011) and thesecond retransmission of the first TB (e.g., via the third resource2021) may be smaller than or equal to 32 sidelink slots (e.g., T <32slots in FIG. 20) or any other quantity of sidelink slots or any otherduration. A first SCI may associate with the initial transmission of thefirst TB. The first SCI may indicate a first T/F resource indication forthe initial transmission of the first TB, the first retransmission ofthe first TB, and the second retransmission of the first TB. The firstSCI may indicate a reservation period of resource reservation for asecond TB, for example, via a fourth resource 2002. A second SCI mayassociate with the first retransmission of the first TB. The second SCImay indicate a second T/F resource indication for the firstretransmission of the first TB (e.g., via the second resource 2011) andthe second retransmission of the first TB (e.g., via a fifth resource2012). The second SCI may indicate the reservation period of resourcereservation for the second TB. A third SCI may associate with the secondretransmission of the first TB. The third SCI may indicate a third T/Fresource indication for the second retransmission of the first TB (e.g.,via a sixth resource 2022). The third SCI may indicate the reservationperiod of resource reservation for the second TB.

FIG. 21 shows an example resource reservation. The example resourcereservation 2110 may be based on sensing/monitoring of resources, by awireless device. A base station may send one or more parameters to thewireless device. The one or more parameters may configure one or morereservation periods (e.g., reservation period 1, reservation period 2,and reservation period 3) of a resource pool. The wireless device mayreceive a first sidelink transmission in a subchannel 2 of a slot 1 in asensing window. SCI of the first sidelink transmission may indicate areservation period (e.g., the reservation period 1) of the one or morereservation periods. The wireless device may determine, based on theSCI, that a subchannel 2 of a slot 2 in a selection window has beenreserved for a sidelink transmission. The wireless device may not selectthe subchannel 2 of slot 2 in the selection window for sending a secondsidelink transmission, for example, based on the determination. Thewireless device may or may not monitor a slot 1 in a sensing window. Thewireless device may not monitor the slot 1, for example, if the wirelessdevice may only have a half-duplex capability of and/or if the wirelessdevice may be sending/transmitting in the slot 1. The wireless devicemay determine the one or more reservation periods of the resource poolas the possible reservation periods of a sidelink transmission via theresource pool. The wireless device may assume resources in slot 2, slot3 and slot 4 might be reserved by a first sidelink transmission in theslot 1 based on the one or more reservation periods. The wireless devicemay not select the resources (e.g., resources shown in dotted boxes inFIG. 21) in the slot 2, the slot 3 and the slot 4 for avoiding potentialresource collision between a second sidelink transmission sent by thewireless device and a possible sidelink transmission indicated by SCI ofthe first sidelink transmission in the slot 1.

FIG. 22 shows an example method of a resource selection. The examplemethod 2200 may be performed by a wireless device for a sidelinktransmission. At step 2210, the wireless device may trigger a resourceselection procedure. The wireless device may trigger the resourceselection procedure, for example, based on a determination that thereare not enough available resources at the wireless device for sending asidelink transmission. At 2220, the wireless device may determine asensing window (e.g., the sensing window shown in FIG. 19) based on thetriggering the resource selection procedure. The wireless device maydetermine a selection window (e.g., the selection window shown in FIG.19) based on the triggering the resource selection procedure. Thewireless device may determine one or more reservation periods forresource reservation.

At step 2230, the wireless device may initialize a candidate resourceset. The candidate resource step may comprise a plurality of candidateresources. The candidate resource set may be the union of candidateresources within the selection window. A candidate resource for thesidelink transmission may be a T/F resource with a size matched to thesidelink transmission. A candidate resource with a size matched to asidelink transmission may indicate that the candidate resource comprisesa quantity of subchannels sufficient to send the data of the sidelinktransmission. A candidate resource may be a single-subframe resource. Acandidate resource may be a single-slot resource.

At step 2240 a, the wireless device may determine first resources,within a sensing window, that are not monitored by the wireless device.The wireless device may not monitor the first resources, for example, ifthe wireless device is performing transmission of other signals via thefirst resources, or if the wireless device is in a sleep mode (e.g.,power saving mode, DRX OFF state, etc.). The wireless device may performa first exclusion 2240 for excluding second resources (e.g., step 2240b)from the candidate resource set based on the first resources and the oneor more reservation periods. The one or more reservation periods may beconfigured/associated with a resource pool of the second resources. Thewireless device may determine the second resources within the selectionwindow, for example, based on the one or more reservation periods. Thesecond resources may be reserved by a transmission sent via the firstresources.

The wireless device may perform a second exclusion 2250 for excludingthird resources from the candidate resource set. SCI may indicate aresource reservation of the third resources. The SCI may furtherindicate a priority value. The wireless device may exclude the thirdresources from the candidate resource set based on an RSRP of the thirdresources being higher than an RSRP threshold. The RSRP threshold may beassociated with the priority value based on a mapping list of RSRPthresholds to priority values (e.g., configured and/or pre-configured tothe wireless device). A base station may send a message to the wirelessdevice for configuring the mapping list. The message may comprise an RRCmessage. The mapping list may be pre-configured for the wireless device.A memory associated with the wireless device may store the mapping list.

At step 2260, the wireless device may determine whether the remainingresources in the candidate resource set (e.g., based on/after performingthe first exclusion 2240 and the second exclusion 2250) are sufficientfor selecting resources for the sidelink transmission and/orretransmission. The determination of whether the remaining resources aresufficient may be based on one or more conditions. For example, thedetermination of whether the remaining resources are sufficient may bebased on a first quantity of remaining radio resources and and a secondquantity of the candidate resources in the candidate resource set beforeperforming the first exclusion and the second exclusion. The wirelessdevice may determine a ratio of the first quantity and the secondquantity. At steps 2260 and 2270, the wireless device may increase theRSRP threshold used to exclude the third resources (e.g., by a quantityY), for example, if the ratio is less than a threshold value (e.g., X%).The wireless device may iteratively re-perform the initialization, thefirst exclusion 2240, and the second exclusion 2250 at least until thecondition is met (e.g., at least until the ratio is greater than thethreshold value). The wireless device may select fourth resources fromremaining candidate resources of the candidate resource set for thesidelink transmission and/or retransmission, at step 2280, for example,if the ratio is greater than a threshold value.

FIG. 23 shows an example of interference between sidelinkcommunications. A wireless device 2310 may send a sidelink transmissionA, via first resources, to a wireless device 2320. SCI of the sidelinktransmission A may indicate a resource assignment and/or a reservationof second resources (e.g., for a future sidelink transmission from thewireless device 2310 to the wireless device 2320). The wireless device2320 may send feedback A to the wireless device 2310, for example, basedon the receipt of the sidelink transmission A.

A wireless device 2330 may trigger a resource selection procedure (e.g.,as shown in FIG. 22) to select third resources for sending a sidelinktransmission B to a wireless device 2340. The wireless device 2330 mayreceive the sidelink transmission A in a sensing window. The wirelessdevice 2330 may determine an RSRP based on a measurement of the sidelinktransmission A. The wireless device 2330 may use the determined RSRP(e.g., of the sidelink transmission A) to determine an estimate of aninterference that the sidelink transmission B may cause to wirelessdevice 2310. The wireless device 2330 may select the third resources,for example, based on the determined RSRP being less than an RSRPthreshold. The wireless device 2330 may select the third resources suchthat the third resources may fully or partially overlap with the secondresources. Using only the determined RSRP of the sidelink transmission Afor selection of third resources for the sidelink transmission B doesnot account for the interference that the sidelink transmission B maycause to wireless device 2320 that receives the sidelink transmission A.The interference to wireless device 2320 may be significant depending onthe distance between wireless device 2330 and wireless device 2320.

A first wireless device may determine/select channel resources (e.g.,for a sidelink transmission) based on various channel measurements(e.g., RSRP). For example, the first wireless device may measure an RSRPfor a sidelink transmission from a second wireless device to a thirdwireless device. The sidelink transmission may comprise transmission viaa PSCCH or a PSSCH. The first wireless device may determine channelresources based on the RSRP (e.g., as described with reference to FIG.23). Selection of channel resources based only on the sidelinktransmission (e.g., from the second wireless device) does not accountfor the extent of interference that a transmission from the firstwireless device may cause to the third wireless device. For example,among the second wireless device and the third wireless device, thethird wireless device may be closer to the first wireless device. Thethird wireless device may be subject to increased interference fromtransmissions by the first wireless device. The first wireless devicemay select and send a signal via a channel resource that may interferewith signal receptions at the third wireless device.

Various examples herein describe enhanced resource selection. A wirelessdevice may perform the enhanced resource selection for sidelinkcommunication (or any other type of communication, such as uplink and/ordownlink communication). The wireless device may determine/selectchannel resources for signal transmission based on measurementsassociated with a signal (e.g., a sidelink signal sent by a secondwireless device) and/or measurements associated with a feedback signal(e.g., a feedback signal, responsive to the sidelink signal, sent by athird wireless device). The wireless device may exclude resources from acandidate resource set based on a feedback measurement (e.g., of afeedback signal associated with sidelink communications). The wirelessdevice may exclude the resources from the candidate resource set, forexample, if a received power of the feedback signal is higher than athreshold value. The wireless device may exclude resources from acandidate resource set, for example, based on a sidelink measurementand/or a feedback measurement. For example, the wireless device maymeasure one or more feedback channels (e.g., PSFCH or any other feedbackchannel(s)), and based on the measurement(s), the wireless device mayselect one or more resources for a sidelink communication with anotherwireless device that may (or may not) overlap with resources associatedwith the feedback channel(s). For example, if the measurement(s)satisfy/satisfies a threshold, the wireless device may (or may not)select the corresponding one or more resources. The wireless device mayselect the one or more resources, for example, if the measurement(s) areless than (or equal to) a threshold. The wireless device may exclude(e.g., not select) the one or more resources, for example, if themeasurement(s) are greater than (or equal to) a threshold. By selectingone or more resources based on the measurement(s) of feedback channel(s)satisfying a threshold, the wireless device may avoid and/or reduce alikelihood of selecting resource(s) that may cause interference withother communications.

A wireless device may exclude the resources from the candidate resourceset based on a received power (e.g., RSRP) of a sidelink signal beinghigher than a first threshold value (e.g., an RSRP threshold value)and/or a received power of a feedback signal being higher than a secondthreshold value. The first threshold value and the second thresholdvalue may be same or different. A wireless device may exclude resourcesfrom a candidate resource set based on an RSRP threshold value. Thewireless device may determine the RSRP threshold based on a receivedpower of a feedback signal. The wireless device may exclude theresources from the candidate resource set, for example, if an RSRP ofthe sidelink signal is higher than the RSRP threshold value. Thewireless device may determine a transmit power for sending a sidelinksignal based on a feedback signal measurement. Excluding resources basedon a feedback signal measurement may provide advantages such as reducedinterference and/or improved sidelink transmission integrity.

A wireless device may determine to trigger an enhanced resourceselection procedure, for example, based on one or more triggeringconditions. A triggering condition may be based on communicationactivity between other wireless devices and/or an urgency of data to betransmitted by a wireless device. For example, a triggering conditionmay be based on at least one of: a channel busy ratio measurement in asensing window, a packet delay budget of a sidelink transmission, and/ora priority of a sidelink transmission. The conditional triggering of theenhanced resource selection process may provide advantages such asreduced power consumption by a wireless device.

FIG. 24 shows an example of an enhanced resource selection procedure.The enhanced resource selection process may reduce interference betweensidelink communications associated with different communication devices.A wireless device 2410 may send a sidelink transmission A via firstresources to a wireless device 2420. SCI of the sidelink transmission Amay indicate a resource assignment and/or a reservation of secondresources for a future sidelink transmission from the wireless device2410 to the wireless device 2420. The wireless device 2420 may send afeedback A to the wireless device 2410, for example, based on (e.g.,after or in response to) the sidelink transmission A.

A wireless device 2430 may trigger the enhanced resource selectionprocedure to select third resources. The third resource may be forsending a sidelink transmission B to a wireless device 2440. Thewireless device 2430 may receive the sidelink transmission A and thefeedback A in a sensing window. The wireless device 2430 may determinethe third resources based on measurements associated with both thesidelink transmission A (e.g., sidelink transmission A measurement) andthe feedback A (e.g., feedback A measurement). The third resources mayor may not overlap with the second resources. The sidelink transmissionB from the wireless device 2430, via the third resources, may notintroduce interference to the wireless device 2420, for example, if thethird resources do not overlap with the second resources. The wirelessdevice 2430 may reduce power for sending the sidelink transmission B viathird resources, for example, if the third resources are partially orfully overlapped with the second resources. The sidelink transmission Bfrom the wireless device 2430, via the third resources, may reduceinterference to the wireless device 2420, such as compared to theinterference that may introduced by other resource selection procedures(e.g., as described above in FIG. 23).

The wireless device 2430 may exclude the second resources from acandidate resource set based on the feedback A measurement. The wirelessdevice 2430 may exclude the second resources from the candidate resourceset, for example, if the feedback A measurement indicates that areceived power of the feedback A is greater than a threshold value. Thewireless device 2430 may exclude the second resources from the candidateresource set based on the sidelink transmission A measurement and/or thefeedback A measurement. The wireless device 2430 may exclude the secondresources from the candidate resource set based on an RSRP of thesidelink transmission A being greater than an RSRP threshold valueand/or a received power of the feedback A being greater than a thresholdvalue. The wireless device 2430 may exclude the second resources fromthe candidate resource set based on an RSRP threshold value. Thewireless device 2430 may determine the RSRP threshold based on areceived power of the feedback A. The wireless device 2430 may excludethe second resources from the candidate resource set, for example, ifthe sidelink transmission A measurement indicates that an RSRP of thefirst resources is greater than the RSRP threshold. The wireless device2430 may determine a transmit power for sending the sidelinktransmission B (e.g., via the third resources) based on the feedback Ameasurement. The wireless device 2430 may send the sidelink transmissionB, via the third resources, using the transmit power. The wirelessdevice 2430 may determine to trigger the enhanced resource selectionprocedure based on a triggering condition. The triggering condition maybe based on a channel busy ratio measurement in the sensing window, apacket delay budget of a sidelink transmission, and/or a priority of asidelink transmission. Implementing the enhanced resource selectionprocedure may help to reduce and/or avoid interference from a firstwireless device (e.g., wireless device 2430) that transmits via a firstsidelink (e.g., sidelink transmission B) to a second wireless device(e.g., wireless device 2420) that receives via a second sidelink (e.g.,sidelink transmission A).

An association mapping between a PSSCH and one or more PSFCH resourcesmay exist. A wireless device may be scheduled, via SCI, with a PSSCHreception (e.g., in one or more sub-channels from a quantity ofN_(subch) ^(PSSCH) sub-channels). The SCI may indicate that the wirelessdevice may send a PSFCH transmission. The PSFCH transmission maycomprise HARQ-ACK information based on the PSSCH reception. The wirelessdevice may provide HARQ-ACK information that comprises ACK or NACK, oronly NACK. The wireless device may be provided a quantity of slots in aresource pool for a period corresponding to PSFCH transmission occasionresources. PSFCH transmissions via the resource pool may be disabled,for example, if the quantity is zero. The wireless device may beindicated (e.g., by higher layers) to not send a PSFCH transmissionbased on the PSSCH reception. The wireless device may provide theHARQ-ACK information in a PSFCH transmission via a resource pool, forexample, if the wireless device performs a PSSCH reception via theresource pool and a field in the SCI (e.g., corresponding to an SCIformat 0-2) scheduling the PSSCH reception indicates that the wirelessdevice is to report HARQ-ACK information for the PSSCH reception. Thewireless device may send the PSFCH transmission in a first slot thatincludes PSFCH resources and is at least a quantity of slots of theresource pool after a last slot of the PSSCH reception. The wirelessdevice may be provided a set of M_(PRB, set) ^(PSFCH) PRBs in a resourcepool for PSFCH transmission in a PRB of the resource pool. For aquantity of N_(subch) sub-channels for the resource pool and a quantityof N_(PSSCH) ^(PSFCH) PSSCH slots associated with a PSFCH slot, thewireless device may allocate the [(i+j·N_(PSSCH)^(PSFCH))·M_(subch, slot) ^(PSFCH), (i+1+j·N_(PSSCH)^(PSFCH))·M_(subch, slot) ^(PSFCH)−1] PRBs from the M_(PRS, set)^(PSFCH)PRBs to slot i and sub-channel j, where M_(subch, slot)^(PSFCH)=M_(PRS, set) ^(PSFCH)/(N_(subch)·N_(PSSCH) ^(PSFCH)),0≤i<N_(PSSCH) ^(PSFCH), 0≤j<N_(subch). The allocation may start in anascending order of i and continue in an ascending order of j. Thewireless device may determine a quantity of PSFCH resources availablefor multiplexing HARQ-ACK information in a PSFCH transmission asR_(PRB, CS) ^(PSFCH)=N_(type) ^(PSFCH)·M_(subch, slot) ^(PSFCH)·N_(CS)^(PSFCH) where N_(CS) ^(PSFCH) is a quantity of cyclic shift pairs forthe resource pool and, based on an indication by higher layers: theN_(subch) ^(PSSCH)·M_(subch, slot) ^(PSFCH) are located in one or moresub-channels from the N_(subch) ^(PSSCH) sub-channels.

The wireless device may use/apply one cyclic shift from a cyclic shiftpair to a sequence used for the PSFCH transmission. The PSFCH resourcesmay be first indexed according to an ascending order of the PRB index,from the N_(type) ^(PSFCH)·M_(subch, slot) ^(PSFCH) PRBs, and thenaccording to an ascending order of the cyclic shift pair index from theN_(CS) ^(PSFCH) cyclic shift pairs. The wireless device may determine anindicator/index of a PSFCH resource for a PSFCH transmission, based on(e.g., after or in response to) a PSSCH reception, using a sequenceassociated with the resource pool. The indicator/index of the PSFCHresource may be determined as (P_(ID)+M_(ID))mod R_(PRB, CS) ^(PSFCH),where P_(ID) is a physical layer source identity (ID) provided by SCIformat 0-2 scheduling the PSSCH reception, M_(ID) is zero or M_(ID) isthe ID of the wireless device performing the PSSCH reception (e.g., asindicated by higher layers).

FIG. 25 shows an example of an association mapping between a PSSCH of asidelink transmission and a PSFCH resource. A resource pool may comprisefour (or any other quantity of) subchannels (X) in the frequency domain.The resource pool may comprise n slots (Y) in the time domain. Theresource pool may comprise up to X*Y T/F resources. A wireless devicemay be configured, by a base station or by a second wireless device orby pre-configuration, with PSFCH resources for HARQ-ACK feedbacks. Forexample, the wireless device may be configured with a period of PSFCHresource (e.g., periodPSFCHresource, k). The period of PSFCH may beconfigured as a quantity of slots. The wireless device may determine thePSFCH resources of the resource pool in every slot with an interval ofthe period of PSFCH resource. The wireless device may determine PSFCHresources of the resource pool in every two slots, for example, ifperiod of the PSFCH resource is two slots. The period of the PSFCHresource may be any other quantity of slots (or frames, subframes,etc.). A PSFCH may be configured with the resource pool. A last symbolof slot k may be the PSFCH. The PSFCH may comprise sixteen candidatePSFCH resources. An association mapping may be configured/pre-configuredfor the resource pool. A first resource of subchannel 1 in slot 1 may beassociate with the candidate PSFCH resource 2. A second resource ofsubchannel 2 in slot 1 may be associated with the candidate PSFCHresource 6. A third resource of subchannel 3 in slot 1 may be associatedwith the candidate PSFCH resource 10. A fourth resource of subchannel 4in slot 1 may be associated with the candidate PSFCH resource 14. Afirst sidelink transmission may be sent via the first resource ofsubchannel 1 in slot 1. The first sidelink transmission may comprise afirst PSCCH transmission and a first PSSCH transmission. A first HARQfeedback corresponding to the first PSSCH transmission may be sent viathe candidate PSFCH resource 2. A second sidelink transmission may besent via the fourth resource of subchannel 4 in slot 1. The secondsidelink transmission may comprise a second PSCCH transmission and asecond PSSCH transmission. A second HARQ feedback corresponding to thesecond PSSCH may be sent via the second candidate PSFCH resource 14. Asshown in FIG. 25, the first sidelink transmission and the secondsidelink transmission may be sent via different resources. The candidatePSFCH resource 2 which is associated with the first PSSCH transmissionof the first sidelink transmission is not overlapped with the candidatePSFCH resource 14 which is associated with the second PSSCH transmissionof the second sidelink transmission.

FIG. 26 shows an example of an association mapping between PSSCH andPSFCH resources. FIG. 26 further shows resource selection based onsensing of a wireless device during a resource selection procedure(e.g., as described with reference to FIG. 21). Similar to FIG. 25, aresource pool may comprise four subchannels in the frequency domain. APSFCH may be configured with the resource pool. The PSFCH may comprisesixteen candidate PSFCH resources. An association mapping may beconfigured/pre-configured for the resource pool. A first resource ofsubchannel 1 in slot 1 may be associated with the candidate PSFCHresource 2. A second resource of subchannel 2 in slot 1 may beassociated with the candidate PSFCH resource 6. A third resource ofsubchannel 3 in slot 1 may be associated with the candidate PSFCHresource 10. A fourth resource of subchannel 4 in slot 1 may beassociated with the candidate PSFCH resource 14. A first sidelinktransmission may be sent via the second resource of the subchannel 2 inthe slot 1. The first sidelink transmission may comprise a first PSCCHtransmission and a first PSSCH transmission. A first HARQ feedbackcorresponding to the first PSSCH transmission of the first sidelinktransmission may be sent via the candidate PSFCH resource 6. The firstsidelink transmission may comprise SCI. The SCI may indicate thereservation period 1 for reserving resources of the subchannel 2 of slot2 for a second sidelink transmission. A wireless device may not receivethe SCI sent in slot 1. For example, the wireless device may sendsidelink transmissions in the slot 1 and, as a result, be unable toreceive the SCI transmitted in slot 1. As another example, the wirelessdevice may receive data from a base station in the slot 1 and, as aresult, be unable to receive the SCI transmitted in slot 1. The wirelessdevice may perform a measurement in the measurement gap. The wirelessdevice may not successfully receive the SCI. The wireless device mayreceive a HARQ-ACK feedback via a PSFCH resource of the PSFCH resources(e.g., resource # 6). The PSFCH resource may be associated with (e.g.,mapped to, or correspond to) a PSSCH resource in subchannel 2 of theslot 1. The wireless device may determine the PSSCH resource based on amapping between one or more PSSCH resources and one or more PSFCHresources. The wireless device may determine that a sidelinktransmission occurred in the subchannel 2 of the slot 1, for example,based on the PSFCH resource. The wireless device may exclude resourcesin a selection window based on the PSSCH resource and one or morereservation periods. As shown in FIG. 26, the wireless device mayexclude subchannel 2 of slot 2, slot 3 and slot 4, corresponding tosubchannel 2 of the slot 1, based on reservation period 1, reservationperiod 2 and reservation period 3.

FIG. 27 shows an example method of a PSFCH-based exclusion in a resourceselection procedure. The example method 2741 may be performed by awireless device. At step 2710, a wireless device may trigger a resourceselection procedure for selecting resources for a sidelink transmission.The wireless device may trigger the resource selection procedure basedon a determination that there are not enough available resources at thewireless device for sending the sidelink transmission. The wirelessdevice may trigger the resource selection procedure based on a counterfor counting a quantity of transmissions. The wireless device may setthe counter to a first value (e.g., an initial value). The counter maybe decreased by one based on (e.g., after) each transmission. Thewireless device may trigger the resource selection procedure (e.g., witha particular probability) if a value of the counter equals zero. Thewireless device may select a sidelink resource for a first sidelinktransmission. The wireless device may determine a collision via thesidelink resource between the first sidelink transmission and a secondsidelink transmission. The wireless device may trigger the resourceselection procedure for re-selecting resources, for example, after or inresponse to determining the collision and before sending the firstsidelink transmission via the sidelink resource.

At step 2720, the wireless device may determine a sensing window basedon the triggering the resource selection procedure. A base station maysend one or more messages to the wireless device for configuring one ormore parameters. The one or more parameters may configure the sensingwindow. The one or more messages may comprise one or more RRC messagesand/or SIBs. A second wireless device may send one or more messages, tothe wireless device, for configuring the one or more parameters of thesensing window. The one or more messages may comprise one or moresidelink RRC messages, sidelink MAC CEs and/or SCI. The one or moreparameters configuring the sensing window may be pre-configured for thewireless device. A memory of the wireless device may store the one ormore parameters configuring the sensing window. The sensing window maybe for a resource selection. The sensing window may be for a resourcere-selection based on determining resource collision.

The wireless device may determine a selection window based on thetriggering the resource selection procedure. A base station may send oneor more messages to the wireless device for configuring one or moreparameters. The one or more parameters may configure the selectionwindow. The one or more messages may comprise one or more RRC messagesand/or SIBs. A second wireless device may send one or more messages tothe wireless device for configuring the one or more parameters of theselection window. The one or more messages may comprise one or moresidelink RRC messages, sidelink MAC CEs and/or SCI. The one or moreparameters, configuring the selection window, may be pre-configured forthe wireless device. A memory of the wireless device may store the oneor more parameters defining the selection window. The selection windowmay be for a resource selection. The selection window may be for aresource re-selection based on determining resource collision.

The wireless device may determine one or more reservation periods forresource reservation. The one or more reservation periods may beconfigured for a resource pool. A base station may send one or moremessages to the wireless device for configuring one or more parameters.The one or more parameters may indicate, to the wireless device, the oneor more reservation periods. The one or more messages may comprise oneor more RRC messages and/or SIBs. A second wireless device may send oneor more messages to the wireless device. The one or more messages maycomprise one or more messages for configuring the one or morereservation periods for the wireless device. The one or more messagesmay comprise one or more sidelink RRC messages, sidelink MAC CEs and/orSCI. The one or more reservation periods may be pre-configured for thewireless device. A memory of the wireless device may store the one ormore reservation periods for resource reservation. The one or morereservation periods may be for resource reservation of an initialtransmission and/or re-transmissions of a same TB. The one or morereservation periods may be for resource reservation of an initialtransmission and/or re-transmissions of a different TB.

At step 2730, the wireless device may initialize a candidate resourceset. The candidate resource set may comprise a plurality of candidateresources. The candidate resource set may be the union of the candidateresources in the selection window. A candidate resource may be asingle-slot T/F resource. The candidate resource may comprise a slot inthe time domain and one or more subchannels in the frequency domain. Thecandidate resource may be a single-subframe T/F resource. The candidateresource may comprise a subframe in the time domain and one or moresubchannels in the frequency domain.

At step 2741 a, the wireless device may determine one or more PSFCHresources in the sensing window. The wireless device may determine theone or more PSFCH resources based on a measurement of the one or morePSFCH resources. The measurement may be based on an energy detection ofthe one or more PSFCH resources. The measurement may correspond toreceived power(s) of signals sent via the one or more PSFCH resources,RSRP(s) of signals sent via the one or more PSFCH resources, receivedsignal strength indications (RSSIs) of the one or more PSFCH resources,reference signal received qualities (RSRQs) of the one or more PSFCHresources, and/or a signal to interference ratios (SINRs) of the one ormore PSFCH resources. The measurements may measure received power(s)associated with the one or more PSFCH resources. For example, thereceived power(s) may be average received power(s) of signals via theone or more PSFCH resources. For example, the received power(s) may beaverage received power(s) of one or more reference signals via the oneor more PSFCH resources. The wireless device may assume that atransmission power of signals via the one or more PSFCH resources isequal to a maximum transmission power (or any other transmission power).The wireless device may compare the received power(s) of the one or morePSFCH resources with one or more threshold values. The wireless devicemay determine the one or more PSFCH resources based on the measurementof the one or more PSFCH resources and the one or more threshold values.A base station may send a message to the wireless device for configuringone or more parameters. The one or more parameters may indicate the oneor more threshold values. The message may comprise an RRC message and/orSIB, a MAC CE, and/or DCI. A second wireless device may send a messageto the wireless device for configuring the one or more threshold values.The message may comprise a sidelink RRC message, a sidelink MAC CEand/or SCI. The one or more threshold values may be pre-configured forthe wireless device. A memory of the wireless device may store the oneor more threshold values.

At step 2741 b, the wireless device may exclude second resources fromthe candidate resource set. The wireless device may exclude the secondresources, for example, based on first resources that are associatedwith: the one or more PSFCH resources in the sensing window and/or theone or more reservation periods for resource reservation. The secondresources may be for a retransmission of a same TB as sent in a previoustransmission via the first resources. The second resources may be for anew transmission of a TB different from a previous transmission via thefirst resources.

At step 2790, the wireless device may select third resources from thecandidate resource set. The wireless device may select the thirdresources, for example, based on excluding the second resources from thecandidate resource set. At step 2791, the wireless device may send thesidelink transmission via the selected third resources. The wirelessdevice may perform a PSFCH-based exclusion 2741 described with respectto FIG. 27, for example, after a second exclusion 2250 as described withrespect to FIG. 22. The wireless device may perform a PSFCH-basedexclusion 2741 as described with respect to FIG. 27, for example, withina second exclusion 2250 as described with respect to FIG. 22.

FIG. 28 shows an example of resource selection based on interferencereduction. The example resource selection may be based on feedbackmeasurement. A wireless device 2810 may send sidelink transmission A,via first resources, to a wireless device 2820. The wireless device 2820may send feedback A to the wireless device 2810, for example, based on(e.g., after or in response to) receiving the sidelink transmission A. Awireless device 2830 may trigger the resource selection procedure toselect third resources for sending a sidelink transmission. The wirelessdevice may select the third resources from a candidate resource set. Thewireless device 2830 may receive, in a sensing window, the feedback Afrom the wireless device 2820. The wireless device 2830 may measure thefeedback A, for example, based on a received power of the feedback Asent via the PSFCH resources. The PSFCH resources may be associated withthe first resources for sending the sidelink transmission A. Thewireless device 2830 may or may not receive, in the sensing window, thesidelink transmission A from the wireless device 2810. The wirelessdevice 2830 may determine the first resources based on an associationmapping between the first resources and the PSFCH resources comprisingthe feedback A (e.g., the PSFCH resources via which the feedback A issent). The wireless device 2830 may determine a distance B from thewireless device 2830, for example, based on a threshold value. A basestation may send a message configuring the threshold value to thewireless device 2830. The message may comprise an RRC message, a SIB, aMAC CE, and/or DCI. A wireless device may send a message, forconfiguring the threshold value, to the wireless device 2830. Themessage comprise be a sidelink RRC message, a sidelink MAC CE and/orSCI. The threshold value may be pre-configured. A memory of the wirelessdevice 2830 may store the pre-configured threshold value. The wirelessdevice 2830 may determine the third resources based on the receivedpower of the feedback A and the threshold value.

The wireless device 2830 may determine second resources that may havebeen reserved by SCI of the sidelink transmission A. The secondresources may be for a future sidelink transmission from the wirelessdevice 2810 to the wireless device 2820. The wireless device maydetermine the second resources, for example, based on the firstresources and one or more reservation periods for resource reservationof a resource pool. For example, a base station may send a message forconfiguring the one or more reservation periods of the resource pool tothe wireless device 2830. The resource pool may comprise the firstresources, the second resources, the third resources, and/or the PSFCHresources. The message may comprise an RRC message, a SIB, a MAC CE,and/or DCI. For example, the one or more reservation periods of theresource pool may be pre-configured to the wireless device 2830. Amemory of the wireless device 2830 may store the one or more reservationperiods of the resource pool.

The wireless device 2830 may exclude the second resources based on oneor more considerations. The wireless device 2830 may exclude the secondresources from the candidate resource set, for example, based on thereceived power of the feedback A being greater than the threshold value.The wireless device 2830 may determine a distance from the wirelessdevice 2830 to the wireless device 2820 being less than the distance B,for example, based on the received power of the feedback A being greaterthan the threshold value. The wireless device 2830 may not exclude thesecond resources from the candidate resource set, for example, based onthe received power of the feedback A being less than the thresholdvalue. The wireless device 2830 may determine a distance from thewireless device 2830 to the wireless device 2820 being larger than thedistance B, for example, based on the received power of the feedback Abeing greater than the threshold value. The wireless device 2830 mayselect the third resources from the candidate resource set based on theexcluding the second resources from the candidate resource set.

The wireless device 2830 may determine one or more distances from thewireless device 2830 based on one or more threshold values. The wirelessdevice 2830 may determine the third resources based on the receivedpower of the feedback A, the one or more threshold values, and/or acondition. The condition may be a probability for excluding the secondresources from the candidate resource set. The probability may be basedon the one or more threshold values. For example, the wireless device2830 may compare the received power of the feedback A EA with a firstthreshold value Th1 and a second threshold value Th2, where Th1<Th2. Thewireless device 2830 may determine a probability P1 for excluding thesecond resources from the candidate resource set if EA≤Th1. The wirelessdevice 2830 may determine a probability P2 for excluding the secondresources from the candidate resource set if Th1<EA<Th2. The wirelessdevice 2830 may determine a probability P3 for excluding the secondresources from the candidate resource set if Th2≤EA. In an example, 1≥P3≥P2 ≥P1 ≥0.

FIG. 29 shows an example method for resource selection. The examplemethod for resource selection 2900 may be of PSFCH-based exclusion ofresources. First resources may be determined concurrently with PSFCHresourres in a sensing window. Steps 2910-2930 and 2990-2991 maycorrespond to steps 2710-2730 and 2790-2791, respectively, describedwith respect to FIG. 27. At step 2910, a wireless device may trigger aresource selection procedure for selecting resources for a sidelinktransmission. The wireless device may trigger the resource selectionprocedure, for example, based on a determination that there are notenough available resources at the wireless device for sending thesidelink transmission. The wireless device may trigger the resourceselection procedure based on a counter. The counter may track a quantityof transmissions. The wireless device may set a first value (e.g., aninitial value) for the counter. The counter value may be decreased byone based on (e.g., after) each transmission. The wireless device maytrigger the resource selection procedure (e.g., with a probability) if asecond value of the counter equals zero. The wireless device may selecta sidelink resource for a first sidelink transmission. The wirelessdevice may determine a collision between the first sidelink transmissionand a second sidelink transmission. The wireless device may trigger theresource selection procedure for re-selecting resources (e.g., based ondetermining the collision), for example, before sending the firstsidelink transmission via the sidelink resource.

At step 2920, the wireless device may determine a sensing window. Thewireless device may determine a sensing window, for example, based onthe triggering the resource selection procedure. A base station may sendone or more messages to the wireless device for configuring one or moreparameters. The one or more parameters may configure the sensing window.The one or more messages may comprise one or more RRC messages and/orSIBs. A second wireless device may send one or more messages to thewireless device for configuring the one or more parameters of thesensing window. The one or more messages may comprise one or morecomprise one or more RRC messages, sidelink MAC CEs, and/or SCI. The oneor more parameters configuring the sensing window may be pre-configuredat the wireless device. A memory of the wireless device may store theone or more parameters configuring the sensing window. The sensingwindow may be for resource selection. The sensing window may be forresource re-selection based on determining resource collision.

The wireless device may determine a selection window, for example, basedon the triggering the resource selection procedure. A base station maysend one or more messages to the wireless device for configuring one ormore parameters. The one or more parameters may configure the selectionwindow. The one or more messages may comprise one or more RRC messagesand/or SIBs. A second wireless device may send one or more messages tothe wireless device for configuring the one or more parameters of theselection window. The one or more messages may comprise one or moresidelink RRC messages, sidelink MAC CEs, and/or SCI. The one or moreparameters configuring the selection window may be pre-configured at thewireless device. A memory of the wireless device may store the one ormore parameters defining the selection window. The selection window maybe for resource selection. The selection window may be for a resourcere-selection based on determining resource collision.

The wireless device may determine one or more reservation periods forresource reservation. The one or more reservation periods may beconfigured for a resource pool. A base station may send one or moremessages to the wireless device for configuring one or more parameters.The one or more parameters may indicate, to the wireless device, the oneor more reservation periods. The one or more messages may comprise oneor more RRC messages and/or SIBs. A second wireless device may send oneor more messages, to the wireless device, for configuring the one ormore reservation periods. The one or more messages may comprise one ormore sidelink RRC messages, sidelink MAC CEs, and/or SCI. The one ormore reservation periods may be pre-configured for the wireless device.A memory of the wireless device may store the one or more reservationperiods for resource reservation. The one or more reservation periodsmay be for resource reservation of an initial transmission and/orre-transmissions of a same TB. The one or more reservation periods maybe for resource reservation for an initial transmission and/or forre-transmissions of a different TB.

At step 2930, the wireless device may initialize a candidate resourceset. The candidate resource set may comprise a plurality of candidateresources. The candidate resource set may be a union of the candidateresources in the selection window. A candidate resource may be asingle-slot T/F resource. The candidate resource may comprise a slot inthe time domain and one or more subchannels in the frequency domain. Thecandidate resource may be a single-subframe T/F resource. The candidateresource may comprise a subframe in the time domain and one or moresubchannels in the frequency domain.

At step 2942 a, the wireless device may determine one or more PSFCHresources in the sensing window. The wireless device may determine theone or more PSFCH resources, for example, based on a measurement ofsignals sent via the one or more PSFCH resources. The measurement may bebased on an energy detection of the one or more PSFCH resources. Themeasurement may correspond to received power(s) of signals sent via theone or more PSFCH resources, RSRP(s) of signals sent via the one or morePSFCH resources, RSSI(s) of the one or more PSFCH resources, RSRQ(s) ofthe one or more PSFCH resources, and/or SINR(s) of the one or more PSFCHresources. The measurement may indicate received power(s) of signalssent via the one or more PSFCH resources. For example, the receivedpower(s) may be average received power(s) of signals sent via the one ormore PSFCH resources. The received power(s) may be average receivedpower(s) of one or more reference signals sent via the one or more PSFCHresources. The wireless device may assume/determine that a transmissionpower of signals sent via the one or more PSFCH resources is a maximumtransmission power (or any other transmission power). The wirelessdevice may compare the received power associated with the one or morePSFCH resources with one or more threshold values. The wireless devicemay determine the one or more PSFCH resources based on the measurementsassociated with the one or more PSFCH resources and the one or morethreshold values. A base station may send a message to the wirelessdevice for configuring one or more parameters. The one or moreparameters may indicate the one or more threshold values. The messagemay comprise an RRC message, a SIB, a MAC CE, and/or DCI. A secondwireless device may send a message to the wireless device forconfiguring the one or more threshold values. The message may comprise asidelink RRC message, a sidelink MAC CE and/or SCI. The one or morethreshold values may be pre-configured for the wireless device. A memoryof the wireless device may store the one or more threshold values.

At step 2942 b, the wireless device may determine first resources in thesensing window. The wireless device may determine the first resources,for example, based on an association mapping between the first resourcesand the one or more PSFCH resources. At step 2942 c, the wireless devicemay exclude second resources from the candidate resource set based onthe first resources, the one or more reservation periods for resourcereservation, and/or a condition. The condition may be a probability ofexcluding the second resources from the candidate resource set. Theprobability may correspond to/based on the one or more threshold values(e.g., as described with respect to FIG. 28). The second resources maybe for a retransmission of a same TB as included in previoustransmission via the first resources. The second resources may be for anew transmission of a different TB than a TB included in a previoustransmission via the first resources.

At step 2990, the wireless device may select third resources from thecandidate resource set. The wireless device may select third resourcesbased on the excluding the second resources from the candidate resourceset. At step 2991, the wireless device may send the sidelinktransmission via the selected third resources.

FIG. 30 shows an example communication for resource selection. Theresource selection may target interference reduction. The resourcesleection may be performed based on feedback measurement and/or sidelinkmeasurement. A wireless device 3010 may send, via first resources,sidelink transmission A to a wireless device 3020. The wireless device3020 may send feedback A to the wireless device 3010, for example, basedon (e.g., after or in response to) receiving the sidelink transmissionA. A wireless device 3030 may trigger the resource selection procedureto select third resources for sending a sidelink transmission. Thewireless device 30303 may select the third resources from the candidateresource set.

The wireless device 3030 may receive, from the wireless device 3010, thesidelink transmission A. The wireless device 3030 may receive thesidelink transmission A in a sensing window. The wireless device 3010may measure an RSRP of the sidelink transmission A, for example, basedon decoding SCI of the sidelink transmission A. The wireless device 3030may determine a distance A from the wireless device 3010 based on a RSRPthreshold value. The SCI may indicate a priority of the sidelinktransmission A. A mapping between one or more RSRP threshold values andone or more priorities may exist and/or may be determined/configured. Afirst priority of the one or more priorities may map to (or associatewith) a first RSRP threshold value of the one or more RSRP thresholdvalues. A second priority of the one or more priorities may map to (orassociate with) a second RSRP threshold value of the one or more RSRPthreshold values. The wireless device 3030 may determine the RSRPthreshold value based on the priority of the sidelink transmission A,and/or the mapping between the one or more RSRP threshold values and theone or more priorities. A base station may send, to the wireless device3030, a message configuring the RSRP threshold value. The message maycomprise an RRC message, an SIB, a MAC CE, and/or DCI. Another wirelessdevice may send, to the wireless device 3030, a message for configuringthe RSRP threshold value. The message may comprise a sidelink RRCmessage, a sidelink MAC CE, and/or SCI. The RSRP threshold value may bepre-configured. A memory of the wireless device 3030 may store thepre-configured RSRP threshold value. The wireless device 3030 maydetermine the third resources based on the RSRP of the sidelinktransmission A and the RSRP threshold value.

The wireless device 3030 may receive the feedback A from the wirelessdevice 3020. The wireless device 3030 may receive the feedback A in thesensing window via PSFCH resources. The wireless device 3030 may measurethe feedback A, for example, based on a received power of the feedbackA. The PSFCH resources may be associated with the first resources usedfor sending the sidelink transmission A. The wireless device 3030 maydetermine a distance B from the wireless device 3020 based on athreshold value. A mapping between one or more threshold values and casttypes may be configured. The cast types may comprise unicast, groupcastoption 1, groupcast option 2, and/or broadcast. For example, a firstthreshold value may map to (or associate with) unicast, a secondthreshold value may map to (or associate with) groupcast option 1, athird threshold value may map to (or associate with) groupcast option 2,and/or a fourth threshold vale may map to (or associate with) broadcast.The wireless device 3030 may determine the threshold value based on acast type of the sidelink transmission A. A base station may send amessage configuring the threshold value for the wireless device 3030.The message may comprise an RRC message, an SIB, a MAC CE, and/or DCI.Another wireless device may send a message for configuring the thresholdvalue to the wireless device 3030. The message may comprise a sidelinkRRC message, a sidelink MAC CE, and/or a SCI. The threshold value may bepre-configured. A memory of the wireless device 3030 may store thepre-configured threshold value. The wireless device 3030 may determinethe third resources based on the received power of the feedback A andthe threshold value.

The wireless device 3030 may determine second resources based ondecoding the SCI of the sidelink transmission A. The SCI may indicateresource assignment of the second resources for a future sidelinktransmission, from the wireless device 3010 to the wireless device 3020,via a resource pool. The future sidelink transmission may be aretransmission of the same TB as sent via the sidelink transmission A.The SCI may indicate a reservation period, of one or more reservationperiods, for reservation of the second resources. The second resourcesmay be for a future sidelink transmission, from the wireless device 3010to the wireless device 3020, via a resource pool. The future sidelinktransmission may be a new transmission of a different TB than as sentvia the sidelink transmission A. For example, a base station may send,to the wireless device 3030, a message for configuring the one or morereservation periods of the resource pool. The resource pool may comprisethe first resources, the second resources, the third resources, and/orthe PSFCH resources. The message may comprise an RRC message, an SIB, aMAC CE, and/or DCI. For example, the one or more reservation periods ofthe resource pool may be pre-configured for the wireless device 3030. Amemory of the wireless device 3030 may store the one or more reservationperiods of the resource pool.

The wireless device 3030 may exclude the second resources from thecandidate resource set based on one or more considerations. The wirelessdevice 3030 may exclude the second resources from the candidate resourceset, for example, if the RSRP of the sidelink transmission A is greaterthan the RSRP threshold value and/or if the received power of thefeedback A is greater than the threshold value. The wireless device 3030may determine that a distance from the wireless device 3030 to thewireless device 3010 is less than the distance A and/or that a distancefrom the wireless device 3030 to the wireless device 3020 is less thanthe distance B, for example, based on the RSRP of the sidelinktransmission A being greater than the RSRP threshold value and thereceived power of the feedback A is greater than the threshold value.The wireless device 3030 may not exclude the second resources from thecandidate resource set, for example, if the RSRP of the sidelinktransmission A is less than the RSRP threshold value and/or the receivedpower of the feedback A is less than the threshold value. The wirelessdevice 3030 may determine that a distance from the wireless device 3030to the wireless device 3010 is larger than the distance A and a distancefrom the wireless device 3030 to the wireless device 3020 is larger thanthe distance B, for example, based on the RSRP of the sidelinktransmission A being less than the RSRP threshold value and the receivedpower of the feedback A being less than the threshold value. Thewireless device 3030 may select the third resources from the candidateresource set based on the exclusion of the second resources from thecandidate resource set.

The wireless device 3030 may determine one or more distances from thewireless device 3030, for example, based on one or more thresholdvalues. The wireless device 3030 may determine the third resources basedon the received power of the feedback A, the one or more thresholdvalues, and a condition. The condition may be a probability forexcluding the second resources from the candidate resource set. Theprobability may be based on the one or more threshold values. Thewireless device 3030 may compare the received power of the feedback A EAwith a first threshold value Th1 and a second threshold value Th2, whereTh1<Th2. The wireless device 3030 may determine a probability P1 forexcluding the second resources from the candidate resource set, forexample, if EA≤Th1. The wireless device 3030 may determine a probabilityP2 for excluding the second resources from the candidate resource set,for example, if Th1<EA<Th2. The wireless device 3030 may determine aprobability P3 for excluding the second resources from the candidateresource set, for example, if Th2≤EA. In an example, 1≥P3≥P2≥P1≥0.

FIG. 31 shows an example method for resource selection. The examplemethod 3100 may comprise PSFCH-based exclusion of resources. Resourcesmay be determined/selected based on a feedback measurement and/or basedon a sidelink measurement. At step 3110, a wireless device may trigger aresource selection procedure for selecting resources for a sidelinktransmission. The wireless device may trigger the resource selectionprocedure, for example, if the wireless device determines that there arenot enough available resources at the wireless device for sending thesidelink transmission. The wireless device may trigger the resourceselection procedure based on a counter for counting a quantity oftransmissions. The wireless device may set a first value (e.g., aninitial value) for the counter. The counter value may be decreased byone (or any other value) based on (e.g., after) each transmission. Thewireless device may trigger the resource selection procedure (e.g., witha probability), for example, if a second value of the counter equalszero (or any other value). The wireless device may select a sidelinkresource for a first sidelink transmission. The wireless device maydetermine a collision between the first sidelink transmission and asecond sidelink transmission. The wireless device may trigger theresource selection procedure for re-selecting resources, for example,based on (e.g., after or in response to) determining the collision andbefore sending the first sidelink transmission via the sidelinkresource.

At step 3120, the wireless device may determine a sensing window basedon the triggering the resource selection procedure. A base station maysend, to the wireless device, one or more messages. The one or moremessages may comprise one or more messages for configuring one or moreparameters. The one or more parameters may configure the sensing window.The one or more messages may comprise one or more RRC messages and/orSIBs. A second wireless device may send one or more messages to thewireless device for configuring the one or more parameters of thesensing window. The one or more messages may comprise one or moresidelink RRC messages, sidelink MAC CEs, and/or SCI. The one or moreparameters configuring the sensing window may be pre-configured for thewireless device. A memory of the wireless device may store the one ormore parameters configuring the sensing window. The sensing window maybe for resource selection. The sensing window may be for resourcere-selection based on determining resource collision.

The wireless device may determine a selection window based on thetriggering the resource selection procedure. A base station may send oneor more messages to the wireless device for configuring one or moreparameters. The one or more parameters may configure the selectionwindow. The one or more messages may comprise one or more RRC messagesand/or SIBs. A second wireless device may send one or more messages tothe wireless device for configuring the one or more parameters of theselection window. The one or more messages may comprise one or moresidelink RRC messages, sidelink MAC CEs and/or SCI. The one or moreparameters, configuring the selection window, may be pre-configured forthe wireless device. A memory of the wireless device may store the oneor more parameters defining the selection window. The selection windowmay be for resource selection. The selection window may be for resourcere-selection based on determining resource collision.

The wireless device may determine one or more reservation periods forresource reservation. The one or more reservation periods may beconfigured for a resource pool. A base station may send one or moremessages to the wireless device for configuring one or more parameters.The one or more parameters may indicate, to the wireless device, the oneor more reservation periods. The one or more messages may comprise oneor more RRC messages and/or SIBs. A second wireless device may send oneor more messages, to the wireless device, for configuring the one ormore reservation periods. The one or more messages may comprise one ormore sidelink RRC messages, sidelink MAC CEs, and/or SCI. The one ormore reservation periods may be pre-configured for the wireless device.A memory of the wireless device may store the one or more reservationperiods for resource reservation. The one or more reservation periodsmay be for resource reservation of an initial transmission and/orre-transmissions of a same TB. The one or more reservation periods maybe for resource reservation of an initial transmission and/orre-transmissions of a different TB.

At step 3130, the wireless device may initialize a candidate resourceset. The candidate resource set may comprise a plurality of candidateresources. The candidate resource set may comprise the union of thecandidate resources in the selection window. A candidate resource maycomprise a single-slot T/F resource. The candidate resource may comprisea slot in the time domain and one or more subchannels in the frequencydomain. The candidate resource may comprise a single-subframe T/Fresource. The candidate resource may comprise a subframe in the timedomain and one or more subchannels in the frequency domain.

At step 3143 a, the wireless device may determine first resources in thesensing window. A second wireless device may send a second sidelinktransmission via the first resources. The second sidelink transmissionmay comprise SCI. The SCI may indicate resource assignment and/orreservation of second resources in the selection window. The SCI mayindicate the resource assignment of the second resources. The secondwireless device may send a third sidelink transmission, via the secondresources. The third sidelink transmission may comprise the same TB assent via the second sidelink transmission. The SCI may indicate areservation period of the one or more reservation periods for theresource reservation of the second resources. The second wireless devicemay send a third sidelink transmission, via the second resources. Thethird sidelink transmission may comprise a different TB than a TB sentvia the second sidelink transmission. The wireless device may measure anRSRP of the second sidelink transmission based on the SCI. The wirelessdevice may compare the RSRP of the second sidelink transmission with anRSRP threshold value. The SCI may indicate a priority of the secondsidelink transmission. A mapping between one or more RSRP thresholdvalues and one or more priorities may be configured/determined. A firstpriority of the one or more priorities may map to (or associate with) afirst RSRP threshold value of the one or more RSRP threshold values. Asecond priority of the one or more priorities may map to (or associatewith) a second RSRP threshold value of the one or more RSRP thresholdvalues. The wireless device may determine the RSRP threshold value basedon the priority of the second sidelink transmission and the mappingbetween the one or more RSRP threshold values and the one or morepriorities. A base station may send a message, to the wireless device,for configuring/determining the RSRP threshold value. The message maycomprise an RRC message, an SIB, a MAC CE, and/or DCI. A third wirelessdevice may send a message, to the wireless device, for configuring theRSRP threshold value. The message may comprise a sidelink RRC message, asidelink MAC CE and/or SCI. The RSRP threshold value(s) may bepre-configured. A memory of the wireless device may store thepre-configured RSRP threshold value(s).

At step 3143 b, the wireless device may determine one or more PSFCHresources in the sensing window. The wireless device may determine theone or more PSFCH resources based on an association mapping between thefirst resources and the one or more PSFCH resources. At step 3143c, thewireless device may exclude second resources from the candidate resourceset. The wireless device may exclude the second resources based on theSCI, a measurement of the one or more PSFCH resources, and/or acondition. The measurement may be based on an energy detection of theone or more PSFCH resources. The measurement may correspond to receivedpower(s) of signals sent via the one or more PSFCH resources, RSRP(s) ofsignals sent via the one or more PSFCH resources, RSSI(s) of the one ormore PSFCH resources, RSRQ(s) of the one or more PSFCH resources, and/orSINR(s) of the one or more PSFCH resources. The measurement may comprisereceived power(s) of signals sent via the one or more PSFCH resources.For example, the received power(s) may be average received power(s) ofsignals sent via the one or more PSFCH resources. For example, thereceived power(s) may be average received power(s) of one or morereference signals sent via the one or more PSFCH resources. The wirelessdevice may assume/determine a transmission power of signals sent via theone or more PSFCH resources to be a maximum transmission power (or anyother transmission power). The wireless device may compare the receivedpower(s) of signals sent via the one or more PSFCH resources with one ormore threshold values. A mapping between one or more threshold valuesand cast types may exist (e.g., may be configured/determined). The casttypes may comprise unicast, groupcast option 1, groupcast option 2,and/or broadcast. For example, a first threshold value may map to (orassociate with) unicast, a second threshold value may map to (orassociate with) groupcast option 1, a third threshold value may map to(or associate with) groupcast option 2, and/or a fourth threshold valemay map to (or associate with) broadcast. The wireless device maydetermine the threshold value based on a cast type of the secondsidelink transmission. A base station may send a message to the wirelessdevice for configuring one or more parameters. The one or moreparameters may indicate the one or more threshold values. The messagemay comprise an RRC message, an SIB, a MAC CE, and/or DCI. A fourthwireless device may send a message to the wireless device forconfiguring the one or more threshold values. The message may comprise asidelink RRC message, a sidelink MAC CE and/or SCI. The one or morethreshold values may be pre-configured for the wireless device. A memoryof the wireless device may store the one or more threshold values. Thecondition may be a probability of excluding the second resources fromthe candidate resource set. The probability may be based on the one ormore threshold values. The wireless device may exclude the secondresources from the candidate resource set if, for example, the RSRP ofthe second sidelink transmission is greater than the RSRP thresholdvalue and/or the received power of signals via the one or more PSFCHresources is greater than a threshold value of the one or more thresholdvalues. At step 3190, the wireless device may select third resourcesfrom the candidate resource set. The wireless device may select thethird resources based on excluding the second resources from thecandidate resource set. At step 3191, the wireless device may send thesidelink transmission via the selected third resources.

FIG. 32 shows an example communication for resource selection. Theresource selection may target interference reduction. The resourceselection may be based on the collective RSRP value of a feedback andsidelink measurement. A wireless device 3210 may send sidelinktransmission A, via first resources, to a wireless device 3220. Thewireless device 3220 may send feedback A to the wireless device 3210,for example, after receiving the sidelink transmission A. A wirelessdevice 3230 may trigger the resource selection procedure to select thirdresources from a candidate resource set. The third resources may be forsending a sidelink transmission.

The wireless device 3230 may receive the sidelink transmission A fromthe wireless device 3210. The wireless device 3230 may receive thesidelink transmission A in a sensing window. The wireless device 3230may measure an RSRP of the sidelink transmission A, for example, basedon decoding SCI of the sidelink transmission A. The wireless device 3230may determine a distance A from the wireless device 3230, for example,based on a RSRP threshold value. The SCI may further indicate a priorityof the sidelink transmission A. A mapping between one or more RSRPthreshold values and one or more priorities may beconfigured/determined. A first priority of the one or more prioritiesmay map to (or associate with) a first RSRP threshold value of the oneor more RSRP threshold values. A second priority of the one or morepriorities may map to (or associate with) a second RSRP threshold valueof the one or more RSRP threshold values. The wireless device 3230 maydetermine the RSRP threshold value, for example, based on the priorityof the sidelink transmission A and the mapping between the one or moreRSRP threshold values and the one or more priorities. A base station maysend a message, to the wireless device 3230, configuring the RSRPthreshold value. The message may comprise an RRC message, an SIB, a MACCE, and/or DCI. A wireless device may send a message, to the wirelessdevice 3230, for configuring the RSRP threshold value. The message maycomprise a sidelink RRC message, a sidelink MAC CE and/or SCI. The RSRPthreshold value(s) may be pre-configured. A memory of the wirelessdevice 3230 may store the pre-configured RSRP threshold value(s). Thewireless device 3230 may determine the third resources based on the RSRPof the sidelink transmission A and the RSRP threshold value(s).

The wireless device 3230 may receive the feedback A, via PSFCHresources, from the wireless device 3220. The wireless device 3230 mayreceive the feedback A in the sensing window. The wireless device 3230may measure the feedback A, for example, based on a received power ofthe feedback A. The PSFCH resources may be associated with the firstresources for sending the sidelink transmission A. The wireless device3230 may determine an offset value of one or more offset values based ona threshold value of one or more threshold values. A mapping between theone or more threshold values and cast types may be configured. The casttypes may comprise unicast, groupcast option 1, groupcast option 2,and/or broadcast. For example, a first threshold value may map to (orassociate with) unicast, a second threshold value may map to (orassociate with) groupcast option 1, a third threshold value may map to(or associate with) groupcast option 2, and/or a fourth threshold valemay map to (or associate with) broadcast. The wireless device 3230 maydetermine the threshold value based on a cast type of the sidelinktransmission A. A mapping between the one or more offset values and theone or more threshold values may be configured/determined. For example,a first offset value of the one or more offset values may map to (orassociate with) a first threshold value of the one or more thresholdvalues, and a second offset value of the one or more offset values maymap to (or associate with) a second threshold value of the one or morethreshold values. The wireless device 3230 may determine the offsetvalue based on the threshold value and the mapping between the one ormore offset values and the one or more threshold values. A base stationmay send a message, to the wireless device 3230, which may configure theone or more offset values and/or the one or more threshold values. Themessage may comprise an RRC message, an SIB, a MAC CE, and/or DCI. Awireless device may send a message, to the wireless device 3230, forconfiguring the one or more offset values and/or the one or morethreshold values. The message may comprise a sidelink RRC message, asidelink MAC CE and/or SCI. The one or more offset values and/or the oneor more threshold values may be pre-configured. A memory of the wirelessdevice 3230 may store the pre-configured one or more offset valuesand/or one or more threshold values. The wireless device 3230 maydetermine the third resources based on the received power of thefeedback A, the offset value, and/or the threshold value.

The wireless device 3230 may determine second resources based ondecoding the SCI of the sidelink transmission A. The SCI may indicateresource assignment of the second resources. The second resources may befor a future sidelink transmission, from the wireless device 3210 to thewireless device 3220, via a resource pool. The future sidelinktransmission may be a retransmission of the same TB as sent in thesidelink transmission A. The SCI may indicate a reservation period, ofone or more reservation periods, for resource reservation of the secondresources for the future sidelink transmission. The future sidelinktransmission may be a new transmission of a different TB than a TB sentin the sidelink transmission A. For example, a base station may send amessage, to the wireless device 3230, for configuring the one or morereservation periods of the resource pool. The resource pool may comprisethe first resources, the second resources, the third resources, and/orthe PSFCH resources. The message may comprise an RRC message, an SIB, aMAC CE, and/or DCI. The one or more reservation periods of the resourcepool may be pre-configured for the wireless device 3230. A memory of thewireless device 3230 may store the one or more reservation periods ofthe resource pool.

The wireless device 3230 may exclude the second resources from thecandidate resource set. The wireless device 3230 may exclude the secondresources from the candidate resource set, for example, based on theRSRP of the sidelink transmission A, the RSRP threshold value, and/orthe offset value. The offset value may be added to the RSRP of thesidelink transmission A. The wireless device 3230 may exclude the secondresources from the candidate resource set, for example, if (the RSRP ofthe sidelink A +the offset value) the RSRP threshold value. The wirelessdevice 3230 may not exclude the second resources from the candidateresource set, for example, if (the RSRP of the sidelink A+the offsetvalue) <the RSRP threshold value. The offset value may be added to theRSRP threshold value. The wireless device 3230 may exclude the secondresources from the candidate resource set, for example, if the RSRP ofthe sidelink A (the RSRP threshold value +the offset value). Thewireless device 3230 may not exclude the second resources from thecandidate resource set, for example, if the RSRP of the sidelink A <(theRSRP threshold value +the offset value). The wireless device 3230 mayselect the third resources from the candidate resource set based onexcluding the second resources from the candidate resource set.

The wireless device 3230 may determine one or more offset values basedon one or more threshold values. The wireless device 3230 may determinethe third resources based on the one or more offset values. The wirelessdevice 3230 may compare the received power of the feedback A EA with afirst threshold value Th1 and a second threshold value Th2, where Th1<Th2. The wireless device 3230 may determine a first offset value, ofthe one or more offset values, for excluding the second resources fromthe candidate resource set, for example, if EA <Th1. The wireless device3230 may determine a second offset value, of the one or more offsetvalues, for excluding the second resources from the candidate resourceset, for example, if Th1 <EA <Th2. The wireless device 3230 maydetermine a third offset value of the one or more offset values forexcluding the second resources from the candidate resource set, forexample, if Th2 ≤EA.

FIG. 33 shows an example method for resource selection. The examplemethod 3300 may comprise PSFCH-based exclusion. At step 3310, a wirelessdevice may trigger a resource selection procedure for selectingresources for a sidelink transmission. The wireless device may triggerthe resource selection procedure based on a determination that there arenot enough available resources at the wireless device for sending thesidelink transmission. The wireless device may trigger the resourceselection procedure based on a counter for counting/determining aquantity of transmissions. The wireless device may set a first value(e.g., an initial value) for the counter. The counter value may bedecreased by one based on (e.g., after) each transmission. The wirelessdevice may trigger the resource selection procedure (e.g., with aprobability), for example, if a second value of the counter equals zero.The wireless device may select/determine a sidelink resource for a firstsidelink transmission. The wireless device may determine a collisionbetween the first sidelink transmission and a second sidelinktransmission. The wireless device may trigger the resource selectionprocedure for re-selecting resources, for example, based on (e.g., afteror in response to) determining the collision and before sending thefirst sidelink transmission via the sidelink resource.

At step 3320, the wireless device may determine a sensing window basedon the triggering the resource selection procedure. A base station maysend one or more messages, to the wireless device, for configuring oneor more parameters. The one or more parameters may configure the sensingwindow. The one or more messages may comprise one or more RRC messagesand/or SIBs. A second wireless device may send one or more messages, tothe wireless device, for configuring the one or more parameters of thesensing window. The one or more messages may comprise one or moresidelink RRC messages, sidelink MAC CEs, and/or SCI. The one or moreparameters configuring the sensing window may be pre-configured for thewireless device. A memory of the wireless device may store the one ormore parameters configuring the sensing window. The sensing window maybe for resource selection. The sensing window may be for resourcere-selection based on determining resource collision.

The wireless device may determine a selection window, for example, basedon the triggering the resource selection procedure. A base station maysend one or more messages, to the wireless device, for configuring oneor more parameters. The one or more parameters may configure theselection window. The one or more messages may comprise one or more RRCmessages and/or SIBs. A second wireless device may send one or moremessages, to the wireless device, for configuring the one or moreparameters of the selection window. The one or more messages maycomprise one or more sidelink RRC messages, sidelink MAC CEs, and/orSCI. The one or more parameters configuring the selection window may bepre-configured for the wireless device. A memory of the wireless devicemay store the one or more parameters defining the selection window. Theselection window may be for resource selection. The selection window maybe for resource re-selection based on determining resource collision.

The wireless device may determine one or more reservation periods forresource reservation. The one or more reservation periods may beconfigured for a resource pool. A base station may send one or moremessages, to the wireless device, for configuring one or moreparameters. The one or more parameters may indicate the one or morereservation periods to the wireless device. The one or more messages maycomprise one or more RRC messages and/or SIBs. A second wireless devicemay send one or more messages, to the wireless device, for configuringthe one or more reservation periods. The one or more messages maycomprise one or more sidelink RRC messages, sidelink MAC CEs, and/orSCI. The one or more reservation periods may be pre-configured for thewireless device. A memory of the wireless device may store the one ormore reservation periods for resource reservation. The one or morereservation periods may be for resource reservation for an initialtransmission and/or re-transmissions of a same TB. The one or morereservation periods may be for resource reservation for an initialtransmission and/or re-transmissions of a different TB.

At step 3330, the wireless device may initialize a candidate resourceset. The candidate resource set may comprise a plurality of candidateresources. The candidate resource set may be the union of the candidateresources in the selection window. A candidate resource may be asingle-slot T/F resource. The candidate resource may comprise a slot inthe time domain and one or more subchannels in the frequency domain. Thecandidate resource may be a single-subframe T/F resource. The candidateresource may comprise a subframe in the time domain and one or moresubchannels in the frequency domain.

At step 3343 a, the wireless device may determine first resources in thesensing window. A second wireless device may send a second sidelinktransmission via the first resources. The second sidelink transmissionmay comprise SCI. The SCI may indicate resource assignment and/orreservation of second resources in the selection window. The SCI mayindicate the resource assignment of the second resources. The secondwireless device may send a third sidelink transmission, via the secondresources. The third sidelink transmission may comprise the same TB assent via the second sidelink transmission. The SCI may indicate areservation period, of the one or more reservation periods, for theresource reservation of the second resources. The second wireless devicemay send a third sidelink transmission, via the second resources. Thethird sidelink transmission may comprise a different TB than as sent viathe second sidelink transmission. The wireless device may measure anRSRP of the second sidelink transmission based on the SCI. The wirelessdevice may compare the RSRP of the second sidelink transmission with anRSRP threshold value. The SCI may further indicate a priority of thesecond sidelink transmission. A mapping between one or more RSRPthreshold values and one or more priorities may be configured. A firstpriority of the one or more priorities may map to (or associate with) afirst RSRP threshold value of the one or more RSRP threshold values. Asecond priority of the one or more priorities may map to (or associatewith) a second RSRP threshold value of the one or more RSRP thresholdvalues. The wireless device may determine the RSRP threshold value basedon the priority of the second sidelink transmission, and the mappingbetween the one or more RSRP threshold values and the one or morepriorities. A base station may send, to the wireless device, a messageconfiguring the RSRP threshold value. The message may comprise an RRCmessage, an SIB, a MAC CE, and/or DCI. A third wireless device may send,to the wireless device, a message for configuring the RSRP thresholdvalue. The message may comprise a sidelink RRC message, a sidelink MACCE and/or SCI. The RSRP threshold value may be pre-configured. A memoryof the wireless device may store the pre-configured RSRP thresholdvalue.

At step 3343 b, the wireless device may determine an offset value of oneor more offset values. The wireless device may determine the offsetvalue based on a measurement of one or more PSFCH resources in thesensing window. The wireless device may determine the one or more PSFCHresources based on an association mapping between the first resourcesand the one or more PSFCH resources. The measurement may be based on anenergy detection of the one or more PSFCH resources. The measurement maycorrespond to received power(s) of signals sent via the one or morePSFCH resources, RSRP(s) of signals sent via the one or more PSFCHresources, RSSI(s) of the one or more PSFCH resources, RSRQ(s) of theone or more PSFCH resources, and/or SINR(s) of the one or more PSFCHresources. The measurement may comprise received power(s) of signals viathe one or more PSFCH resources. For example, the received power(s) maybe average received power(s) of signals sent via the one or more PSFCHresources. For example, the received power(s) may be average receivedpower(s) of one or more reference signals sent via the one or more PSFCHresources. The wireless device may assume that a transmission power ofsignals via the one or more PSFCH resources is a maximum transmissionpower (or any other transmission power). The wireless device may comparethe received power(s) of signals sent via the one or more PSFCHresources with one or more threshold values. The wireless device maydetermine the offset value based on a threshold value of the one or morethreshold values. A mapping between the one or more threshold values andcast types may be configured. The cast types may comprise unicast,groupcast option 1, groupcast option 2 and broadcast. For example, afirst threshold value may map to (or associate with) unicast, a secondthreshold value may map to (or associate with) groupcast option 1, athird threshold value may map to (or associate with) groupcast option 2,and a fourth threshold vale may map to (or associate with) broadcast.The wireless device may determine the threshold value based on a casttype of the second sidelink transmission. A mapping between the one ormore offset values and the one or more threshold values may beconfigured. For example, a first offset value of the one or more offsetvalues may map to (or associate with) a first threshold value of the oneor more threshold values, and a second offset value of the one or moreoffset values may map to (or associate with) a second threshold value ofthe one or more threshold values. The wireless device may determine theoffset value based on the threshold value, and the mapping between theone or more offset values and the one or more threshold values. A basestation may send a message, to the wireless device, for configuring oneor more parameters. The one or more parameters may indicate the one ormore offset values and/or the one or more threshold values. The messagemay comprise an RRC message, an SIB, a MAC CE, and/or DCI. A fourthwireless device may send a message, to the wireless device, forconfiguring the one or more offset values and/or the one or morethreshold values. The message may comprise a sidelink RRC message, asidelink MAC CE and/or SCI. The one or more offset values and/or the oneor more threshold values may be pre-configured for the wireless device.A memory of the wireless device may store the one or more offset valuesand/or the one or more threshold values.

At step 3343c, the wireless device may exclude second resources from thecandidate resource set. The wireless device may exclude second resourcesbased on the offset value. The offset value may be added to the RSRP ofthe second sidelink transmission. The wireless device may exclude thesecond resources from the candidate resource set, for example, if (theRSRP of the second sidelink transmission +the offset value) the RSRPthreshold value. The wireless device may not exclude the secondresources from the candidate resource set, for example, if (the RSRP ofthe second sidelink transmission +the offset value) <the RSRP thresholdvalue. The offset value may be added to the RSRP threshold value of theone or more RSRP threshold values. The wireless device may exclude thesecond resources from the candidate resource set, for example, if theRSRP of the second sidelink transmission ≥(the RSRP threshold value +theoffset value). The wireless device may not exclude the second resourcesfrom the candidate resource set, for example, if the RSRP of the secondsidelink transmission <(the RSRP threshold value +the offset value). Thewireless device may select the third resources from the candidateresource set based on the excluding the second resources from thecandidate resource set. At step 3390, the wireless device may selectthird resources from the candidate resource set. The wireless device mayselect the third resources based on the excluding the second resourcesfrom the candidate resource set. At step 3391, the wireless device maysend the sidelink transmission via the selected third resources.

FIG. 34 shows an example method for resource selction. The examplemethod 3400 may comprise a PSFCH-based exclusion of resources. At step3410, a wireless device may trigger a resource selection procedure forselecting resources for a sidelink transmission. At step 3420, thewireless device may determine a sensing window, for example, based onthe triggering the resource selection procedure. The wireless device maydetermine a selection window, for example, based on the triggering theresource selection procedure. The wireless device may determine one ormore reservation periods for resource reservation. At step 3430, thewireless device may initialize a candidate resource set to be a set ofcandidate resources. The candidate resource set may be the union of thecandidate resources in the selection window.

At step 3431, the wireless device may determine to trigger a PSFCH-basedexclusion procedure based on a condition. The condition may comprise achannel busy ratio (CBR) in the sensing window being greater than a CBRthreshold value. The condition may comprise a packet delay budget (PDB)for the sidelink transmission being less than a PDB threshold value. Thecondition may comprise a priority of the sidelink transmission beinggreater than a priority threshold value. A base station may send amessage, to the wireless device, for configuring one or more parameters.The one or more parameters may indicate the CBR threshold value, the PDBthreshold value, and/or the priority threshold value. The message maycomprise an RRC message, a SIB, a MAC CE, and/or DCI. A second wirelessdevice may send a message to the wireless device for configuring the CBRthreshold value, the PDB threshold value, and/or the priority thresholdvalue. The message may comprise a sidelink RRC message, a sidelink MACCE, and/or SCI. The CBR threshold value, the PDB threshold value, and/orthe priority threshold value may be pre-configured for the wirelessdevice. A memory of the wireless device may store the CBR thresholdvalue, the PDB threshold value, and/or the priority threshold value.

The wireless device may determine one or more PSFCH resources in thesensing window, for example, if the condition is met, at step 3444a. Thewireless device may determine the one or more PSFCH resources based on ameasurement of the one or more PSFCH resources. The measurement may bebased on an energy detection of the one or more PSFCH resources. Themeasurement may correspond to received power(s) of signals sent via theone or more PSFCH resources, RSRPs of signals sent via the one or morePSFCH resources, RSSIs of the one or more PSFCH resources, RSRQs of theone or more PSFCH resources, and/or SINRs of the one or more PSFCHresources. The measurement may correspond to received power(s) ofsignals sent via the one or more PSFCH resources. For example, thereceived power(s) may be average received power(s) of signals sent viathe one or more PSFCH resources. For example, the received power(s) maybe average received power(s) of one or more reference signals sent viathe one or more PSFCH resources. The wireless device mayassume/determine that a transmission power of signals sent via the oneor more PSFCH resources is a maximum transmission power (or any othertransmission power). The wireless device may compare the receivedpower(s) of signals sent via the one or more PSFCH resources with one ormore threshold values. The wireless device may determine the one or morePSFCH resources, for example, based on the measurement of the one ormore PSFCH resources and the one or more threshold values. A basestation may send a message, to the wireless device, for configuring oneor more parameters. The one or more parameters may indicate the one ormore threshold values. The message may comprise an RRC message, an SIB,a MAC CE, and/or DCI. A second wireless device may send a message, tothe wireless device, for configuring the one or more threshold values.The message may comprise a sidelink RRC message, a sidelink MAC CEand/or SCI. The one or more threshold values may be pre-configured forthe wireless device. A memory of the wireless device may store the oneor more threshold values.

At step 3444 b, the wireless device may exclude second resources fromthe candidate resource set. The wireless device may exclude the secondresources, for example, based on first resources (e.g., that areassociated with the one or more PSFCH resources) in the sensing windowand/or the one or more reservation periods for resource reservation. Thesecond resources may be for a retransmission of the same TB as sent in aprevious transmission via the first resources. The second resources maybe for a new transmission of a different TB than a TB sent in a previoustransmission via the first resources.

At step 3490, the wireless device may select third resources from thecandidate resource set based on the excluding the second resources fromthe candidate resource set. The wireless device may bypass thePSFCH-based exclusion 3444 and perform steps 3490 and 3491, if, forexample, the condition is not met in step 3431. At step 3491, thewireless device may send the sidelink transmission via the selectedthird resources.

The PSFCH-based exclusion procedure described herein may or may not beperformed in addition to the resource exclusion procedure described withrespect to FIG. 22, for example, based on the condition being met. Asshown in step 3432, the wireless device may perform resource selectionand transmission based on the resource exclusion procedure describedwith respect to FIG. 22 (and not perform the PSFCH-based exclusionprocedure), for example, if the condition is not met.

FIG. 35 shows an example method for power control for a sidelinktransmission. The example method 3500 may be based on measurementsperformed on PSFCH resources. At step 3510, a wireless device maytrigger a resource selection procedure for selecting resources for asidelink transmission. The wireless device may trigger the resourceselection procedure, for example, if the wireless device determininesthat not enough resources are available at the wireless device forsending the sidelink transmission. The wireless device may trigger theresource selection procedure based on a counter for counting a quantityof transmissions. The wireless device may set a first value (e.g., aninitial value) for the counter. The counter value may be decreased byone based on (e.g., after) each transmission. The wireless device maytrigger the resource selection procedure (e.g., based on a probability)for example, if a second value of the counter equals zero. The wirelessdevice may select a sidelink resource for a first sidelink transmission.The wireless device may determine a collision between the first sidelinktransmission and a second sidelink transmission. The wireless device maytrigger the resource selection procedure for re-selecting resources, forexample, based on (e.g., after or in response to) determining thecollision and before sending the first sidelink transmission via thesidelink resource.

At step 3520, the wireless device may determine a sensing window basedon the triggering the resource selection procedure. A base station maysend one or more messages, to the wireless device, for configuring oneor more parameters. The one or more parameters may configure the sensingwindow. The one or more messages may comprise one or more RRC messagesand/or SIBs. A second wireless device may send one or more messages, tothe wireless device, for configuring the one or more parameters of thesensing window. The one or more messages may comprise one or moresidelink RRC messages, sidelink MAC CEs, and/or SCI. The one or moreparameters configuring the sensing window may be pre-configured for thewireless device. A memory of the wireless device may store the one ormore parameters configuring the sensing window. The sensing window maybe for resource selection. The sensing window may be for resourcere-selection based on determining resource collision.

The wireless device may determine a selection window, for example, basedon the triggering the resource selection procedure. A base station maysend one or more messages, to the wireless device, for configuring oneor more parameters. The one or more parameters may configure theselection window. The one or more messages may comprise one or more RRCmessages and/or SIBs. A second wireless device may send one or moremessages, to the wireless device, for configuring the one or moreparameters of the selection window. The one or more messages maycomprise one or more sidelink RRC messages, sidelink MAC CEs, and/orSCI. The one or more parameters configuring the selection window may bepre-configured for the wireless device. A memory of the wireless devicemay store the one or more parameters defining the selection window. Theselection window may be for resource selection. The selection window maybe for resource re-selection based on determining resource collision.

The wireless device may determine one or more reservation periods forresource reservation. The one or more reservation periods may beconfigured for a resource pool. A base station may send one or moremessages, to the wireless device, for configuring one or moreparameters. The one or more parameters may indicate the one or morereservation periods to the wireless device. The one or more messages maycomprise one or more RRC messages and/or SIBs. A second wireless devicemay send one or more messages, to the wireless device, for configuringthe one or more reservation periods. The one or more messages maycomprise one or more sidelink RRC messages, sidelink MAC CEs, and/orSCI. The one or more reservation periods may be pre-configured for thewireless device. A memory of the wireless device may store the one ormore reservation periods for resource reservation. The one or morereservation periods may be for resource reservation for an initialtransmission and/or re-transmissions of a same TB. The one or morereservation periods may be for resource reservation for an initialtransmission and/or re-transmissions of a different TB.

At step 3530, the wireless device may initialize a candidate resourceset. The candidate resource set may comprise a plurality of candidateresources. The candidate resource set may comprise the union of thecandidate resources in the selection window. A candidate resource maycomprise a single-slot T/F resource. The candidate resource may comprisea slot in the time domain and one or more subchannels in the frequencydomain. The candidate resource may comprise a single-subframe T/Fresource. The candidate resource may comprise a subframe in the timedomain and one or more subchannels in the frequency domain.

At step 3545 a, the wireless device may determine one or more PSFCHresources in the sensing window. The wireless device may determine theone or more PSFCH resources based on a measurement of the one or morePSFCH resources. The measurement may be based on an energy detection ofthe one or more PSFCH resources. The measurement may correspond toreceived power(s) of signals sent via the one or more PSFCH resources,RSRP(s) of signals sent via the one or more PSFCH resources, RSSI(s) ofthe one or more PSFCH resources, RSRQ(s) of the one or more PSFCHresources, and/or SINR(s) of the one or more PSFCH resources. Themeasurement may correspond to received power(s) of signals sent via theone or more PSFCH resources. For example, the received power(s) maycomprise average received power(s) of signals sent via the one or morePSFCH resources. For example, the received power(s) may comprise averagereceived power(s) of one or more reference signals sent via the one ormore PSFCH resources. The wireless device may assume that a transmissionpower of signals sent via the one or more PSFCH resources is a maximumtransmission power (or any other transmission power). The wirelessdevice may compare the received power(s) of signals sent via the one ormore PSFCH resources with one or more threshold values. The wirelessdevice may determine the one or more PSFCH resources based on themeasurement of the one or more PSFCH resources and the one or morethreshold values. A base station may send a message to the wirelessdevice for configuring one or more parameters. The one or moreparameters may indicate the one or more threshold values. The messagemay comprise an RRC message, an SIB, a MAC CE, and/or DCI. A secondwireless device may send a message to the wireless device forconfiguring the one or more threshold values. The message may comprise asidelink RRC message, a sidelink MAC CE and/or SCI. The one or morethreshold values may be pre-configured for the wireless device. A memoryof the wireless device may store the one or more threshold values.

At step 3545 b, the wireless device may determine first resources in thesensing window. The wireless device may determine the first resourcesbased on an association mapping between the first resources and the oneor more PSFCH resources. At step 3545 c, the wireless device maydetermine second resources (e.g., based on the first resources) and/orthe one or more reservation periods for resource reservation. Thewireless device may not receive a second sidelink transmission via thefirst resources. The wireless device may determine the second resources(e.g., that might be reserved by SCI of the second sidelink transmissionvia the first resources) and one or more reservation periods forresource reservation of a resource pool. For example, a base station maysend, to the wireless device, a message for configuring the one or morereservation periods of the resource pool. The resource pool may comprisethe first resources, the second resources, the third resources, and thePSFCH resources. The message may comprise an RRC message, an SIB, a MACCE, and/or DCI. For example, the one or more reservation periods of theresource pool may be pre-configured for the wireless device. A memory ofthe wireless device may store the one or more reservation periods of theresource pool. The wireless device may receive a second sidelinktransmission via the first resources. The second sidelink transmissionmay comprise SCI. The SCI may indicate resource assignment and/orreservation of the second resources in the selection window. The SCI mayindicate the resource assignment of the second resources. The secondwireless device may send a third sidelink transmission, via the secondresources. The third sidelink transmission may comprise the same TB assent via the second sidelink transmission. The SCI may indicate areservation period of the one or more reservation periods for theresource reservation of the second resources. The second wireless devicemay send a third sidelink transmission, via the second resources. Thethird sidelink transmission may comprisea different TB than a TB sentvia the second sidelink transmission.

At step 3545 d, the wireless device may send the sidelink transmissionvia the second resources. The wireless device may use a transmissionpower for sending the sidelink transmission. The wireless device maydetermine the transmission power based on the measurement of the one ormore PSFCH resources. The wireless device may determine a firsttransmission power for sending the sidelink transmission, for example,based on the received power of the one or more PSFCH resources beinggreater than a threshold value of the one or more threshold values. Thewireless device may determine a second transmission power for sendingthe sidelink transmission, for example, based on the received power ofthe one or more PSFCH resources being less than the threshold value ofthe one or more threshold values. The first transmission power may beless than the second transmission power.

FIG. 36 shows an example method for power control for a sidelinktransmission. The example method 3600 may use one or more conditions fortriggering PSFCH-based power control. The PSFCH-based power control maybe used with one or more resource selection procedures as describedherein. At step 3610, a wireless device may trigger a resource selectionprocedure for selecting resources for a sidelink transmission. Thewireless device may trigger the resource selection procedure, forexample, based on a determination that not enough available resourcesare available at the wireless device for sending the sidelinktransmission. The wireless device may trigger the resource selectionprocedure based on a counter for counting a quantity of transmissions.The wireless device may set a first value (e.g., an initial value) forthe counter. The first value of the counter may be decreased by oneafter each transmission. The wireless device may trigger the resourceselection procedure (e.g., based on a probability), for example, if asecond value of the counter equals zero. The wireless device may selecta sidelink resource for a first sidelink transmission. The wirelessdevice may determine a collision between the first sidelink transmissionand a second sidelink transmission. The wireless device may trigger theresource selection procedure for re-selecting resources, for example,based on (e.g., after or in response to) determining the collision andbefore sending the first sidelink transmission via the sidelinkresource.

At step 3620, the wireless device may determine a sensing window basedon the triggering the resource selection procedure. A base station maysend one or more messages, to the wireless device, for configuring oneor more parameters. The one or more parameters may configure the sensingwindow. The one or more messages may comprise one or more RRC messagesand/or SIBs. A second wireless device may send one or more messages, tothe wireless device, for configuring the one or more parameters of thesensing window. The one or more messages may comprise one or moresidelink RRC messages, sidelink MAC CEs, and/or SCI. The one or moreparameters configuring the sensing window may be pre-configured for thewireless device. A memory of the wireless device may store the one ormore parameters configuring the sensing window. The sensing window maybe for resource selection. The sensing window may be for resourcere-selection based on determining resource collision.

The wireless device may determine a selection window based on thetriggering the resource selection procedure. A base station may send oneor more messages, to the wireless device, for configuring one or moreparameters. The one or more parameters may configure the selectionwindow. The one or more messages may comprise one or more RRC messagesand/or SIBs. A second wireless device may send one or more messages, tothe wireless device, for configuring the one or more parameters of theselection window. The one or more messages may comprise one or moresidelink RRC messages, sidelink MAC CEs, and/or SCI. The one or moreparameters configuring the selection window may be pre-configured forthe wireless device. A memory of the wireless device may store the oneor more parameters defining the selection window. The selection windowmay be for resource selection. The selection window may be for resourcere-selection based on determining resource collision.

The wireless device may determine one or more reservation periods forresource reservation. The one or more reservation periods may beconfigured for a resource pool. A base station may send one or moremessages, to the wireless device, for configuring one or moreparameters. The one or more parameters may indicate, to the wirelessdevice, the one or more reservation periods. The one or more messagesmay comprise one or more RRC messages and/or SIBs. A second wirelessdevice may send one or more messages, to the wireless device, forconfiguring the one or more reservation periods. The one or moremessages may comprise one or more sidelink RRC messages, sidelink MACCEs, and/or SCI. The one or more reservation periods may bepre-configured for the wireless device. A memory of the wireless devicemay store the one or more reservation periods for resource reservation.The one or more reservation periods may be for resource reservation foran initial transmission and/or re-transmissions of a same TB. The one ormore reservation periods may be for resource reservation for an initialtransmission and/or re-transmissions of a different TB.

At step 3630, the wireless device may initialize a candidate resourceset. The candidate resource set may comprise a plurality of candidateresources. The candidate resource set may be the union of the candidateresources in the selection window. A candidate resource may be asingle-slot T/F resource. The candidate resource may comprise a slot inthe time domain and one or more subchannels in the frequency domain. Thecandidate resource may be a single-subframe T/F resource. The candidateresource may comprise a subframe in the time domain and one or moresubchannels in the frequency domain.

At step 3651, the wireless device may determine to trigger a PSFCH-basedpower control 3645 based on a condition. The wireless device maydetermine (e.g., step 3652) not to trigger the PSFCH-based power control3645 if the condition is not met. The condition may be a CBR in thesensing window being greater than a CBR threshold value. The conditionmay be a PDB for the sidelink transmission being smaller than a PDBthreshold value. The condition may be a priority of the sidelinktransmission being greater than a priority threshold value. A basestation may send a message, to the wireless device, for configuring oneor more parameters. The one or more parameters may indicate the CBRthreshold value, the PDB threshold value, and/or the priority thresholdvalue. The message may comprise an RRC message, an SIB, a MAC CE, and/orDCI. A second wireless device may send a message, to the wirelessdevice, for configuring the CBR threshold value, the PDB thresholdvalue, and/or the priority threshold value. The message may comprise asidelink RRC message, a sidelink MAC CE, and/or SCI. The CBR thresholdvalue, the PDB threshold value, and/or the priority threshold value maybe pre-configured for the wireless device. A memory of the wirelessdevice may store the CBR threshold value, the PDB threshold value,and/or the priority threshold value.

At step 3645, the wireless device may determine one or more PSFCHresources in the sensing window, for example, based on the conditionbeing met. The wireless device may determine the one or more PSFCHresources based on a measurement of the one or more PSFCH resources. Themeasurement may be based on an energy detection of the one or more PSFCHresources. The measurement may correspond to received power(s) ofsignals sent via the one or more PSFCH resources, RSRP(s) of signalssent via the one or more PSFCH resources, RSSI(s) of the one or morePSFCH resources, RSRQ(s) of the one or more PSFCH resources, and/orSINR(s) of the one or more PSFCH resources. The measurement maycorrespond to received power(s) of signals sent via the one or morePSFCH resources. For example, the received power(s) may comprise averagereceived power(s) of signals sent via the one or more PSFCH resources.For example, the received power(s) may comprise average receivedpower(s) of one or more reference signals sent via the one or more PSFCHresources. The wireless device may assume that a transmission power ofsignals sent via the one or more PSFCH resources is a maximumtransmission power (or any other transmission power). The wirelessdevice may compare the received power(s) of signals sent via the one ormore PSFCH resources with one or more threshold values. The wirelessdevice may determine the one or more PSFCH resources based on themeasurement of the one or more PSFCH resources and the one or morethreshold values. A base station may send a message to the wirelessdevice for configuring one or more parameters. The one or moreparameters may indicate the one or more threshold values. The messagemay comprise an RRC message, an SIB, a MAC CE, and/or DCI. A secondwireless device may send a message to the wireless device forconfiguring the one or more threshold values. The message may comprise asidelink RRC message, a sidelink MAC CE, and/or SCI. The one or morethreshold values may be pre-configured for the wireless device. A memoryof the wireless device may store the one or more threshold values.

At step 3645 b, the wireless device may determine first resources in thesensing window. The wireless device may determine the first resourcesbased on an association mapping between the first resources and the oneor more PSFCH resources. At step 3645 c, the wireless device maydetermine second resources (e.g., based on the first resources) and theone or more reservation periods for resource reservation. The wirelessdevice may not receive a second sidelink transmission via the firstresources. The wireless device may determine the second resources (e.g.,that might be reserved by SCI of the second sidelink transmission viathe first resources) and one or more reservation periods for resourcereservation of a resource pool. For example, a base station may send, tothe wireless device, a message for configuring the one or morereservation periods of the resource pool. The resource pool may comprisethe first resources, the second resources, the third resources, and/orthe PSFCH resources. The message may comprise an RRC message, an SIB, aMAC CE, and/or DCI. For example, the one or more reservation periods ofthe resource pool may be pre-configured for the wireless device. Amemory of the wireless device may store the one or more reservationperiods of the resource pool. The wireless device may receive a secondsidelink transmission via the first resources. The second sidelinktransmission may comprise SCI. The SCI may indicate resource assignmentand/or reservation of the second resources in the selection window. TheSCI may indicate the resource assignment of the second resources. Thesecond wireless device may send a third sidelink transmission, via thesecond resources. The third sidelink transmission may comprise the sameTB as sent via the second sidelink transmission. The SCI may indicate areservation period of the one or more reservation periods for theresource reservation of the second resources. The second wireless devicemay send a third sidelink transmission via the second resources. Thethird sidelink transmission may comprise a different TB than a TB sentvia the second sidelink transmission.

At step 3645d, the wireless device may send the sidelink transmissionvia the second resources. The wireless device may send the sidelinktransmission using a transmission power. The wireless device maydetermine the transmission power based on the measurement of the one ormore PSFCH resources. The wireless device may determine a firsttransmission power for sending the sidelink transmission, for example,based on the received power of the one or more PSFCH resources beinggreater than a threshold value of the one or more threshold values. Thewireless device may determine a second transmission power for sendingthe sidelink transmission , for example, based on the received power ofthe one or more PSFCH resources being less than the threshold value ofthe one or more threshold values. The first transmission power may beless than the second transmission power.

A wireless device may trigger a resource selection procedure for asidelink transmission. The wireless device may determine a sensingwindow, for example, based on the triggering the resource selectionprocedure. The wireless device may determine a selection window, forexample, based on the triggering the resource selection procedure. Thewireless device may determine one or more reservation periods forresource reservation. The wireless device may initialize a candidateresource set comprising candidate resources in the selection window. Thewireless device may determine one or more PSFCH resources in the sensingwindow based on a measurement of the one or more PSFCH resources. Thewireless device may exclude second resources from the candidate resourceset based on first resources in the sensing window and the one or morereservation periods. The first resources may be associated with the oneor more PSFCH resources. The wireless device may select third resourcesfrom the candidate resource set based on the excluding the secondresources from the candidate resource set. The wireless device may sendthe sidelink transmission via the third resources. The measurement maybe based on an energy detection of the one or more PSFCH resources. Themeasurement may measure a received power of signals sent via the one ormore PSFCH resources.

The wireless device may receive one or more RRC messages and/or SIBs.The one or more RRC messages and/or SIBs may comprise one or moreparameters. The one or more parameters may indicate one or morethreshold values. The wireless device may determine the one or morePSFCH resources in the sensing window, for example, based on thereceived power of the one or more PSFCH resources being greater than athreshold value of the one or more threshold values. The wireless devicemay determine a probability for excluding the second resources from thecandidate resource set based on the received power of the one or morePSFCH resources and the one or more threshold values.

The wireless device may receive a first sidelink transmission via thefirst resources. The first sidelink transmission may comprise SCI. TheSCI may comprise one or more parameters indicating resource assignmentof the second resources for a second sidelink transmission. The secondsidelink transmission may comprise a same TB as sent in the firstsidelink transmission. The SCI may comprise one or more parametersindicating resource reservation of the second resources for a secondsidelink transmission. The second sidelink transmission may comprise adifferent TB than a TB sent via the first sidelink transmission.

The one or more RRC messages and/or SIBs may further comprise one ormore second parameters. The one or more second parameters may indicate amapping between one or more RSRP threshold values and one or morepriorities. The SCI may further indicate a priority of the firstsidelink transmission. The wireless device may determine an RSRPthreshold value, of the one or more RSRP threshold values, for example,based on the mapping between the one or more RSRP threshold values andthe one or more priorities, and the priority of the first sidelinktransmission. The wireless device may exclude the second resources fromthe candidate resource set based on a RSRP of the first sidelinktransmission being greater than the RSRP threshold value, and/or thereceived power of the one or more PSFCH resources being greater than thethreshold value.

The one or more RRC messages and/or SIBs may further comprise one ormore third parameters. The one or more third parameters may indicate amapping between one or more threshold values and cast types. Thewireless device may determine the threshold value, for example, based onthe mapping between the one or more threshold values and the cast types,and a cast type of the first sidelink transmission.

The one or more RRC messages and/or SIBs may comprise one or more fourthparameters. The one or more fourth parameters may indicate one or moreoffset values. The wireless device may determine an offset value of theone or more offset values, for example, based on the received power ofthe one or more PSFCH resources and the one or more threshold values.The wireless device may exclude the second resources from the candidateresource set, for example, based on a summation of an RSRP of the firstsidelink transmission and the offset value being greater than the RSRPthreshold value. The wireless device may exclude the second resourcesfrom the candidate resource set, for example, based on an RSRP of thefirst sidelink transmission being greater than a summation of the offsetvalue and the RSRP threshold value.

The one or more RRC messages and/or SIBs may comprise one or more fifthparameters. The one or more fifth parameters may indicate a mappingbetween the one or more threshold values and cast types. The wirelessdevice may determine the offset value, for example, based on the mappingbetween one or more threshold values and the cast types, and a cast typeof the first sidelink transmission.

A wireless device may trigger a resource selection procedure for asidelink transmission. The wireless device may determine a sensingwindow, for example, based on the triggering the resource selectionprocedure. The wireless device may determine a selection window, forexample, based on the triggering the resource selection procedure. Thewireless device may determine one or more reservation periods forresource reservation. The wireless device may determine a received powerof signals sent one or more PSFCH resources in the sensing window. Thewireless device may determine first resources in the sensing window.Tthe first resources may be associated with the one or more PSFCHresources. The wireless device may determine second resources in theselection window based on the first resources and the one or morereservation periods. The wireless device may send the sidelinktransmission via the second resources using a transmission power. Thetransmission power may be based on the received power of signals sentvia the one or more PSFCH resources.

A wireless device may trigger a resource selection procedure for asidelink transmission. The wireless device may determine a sensingwindow, for example, based on the triggering the resource selectionprocedure. The wireless device may determine a selection window, forexample, based on the triggering the resource selection procedure. Thewireless device may receive SCI via first resources in the sensingwindow. The SCI may indicate resource assignment of second resources inthe selection window. The wireless device may determine a received powerof signals sent via one or more PSFCH resources in the sensing window.The one or more PSFCH resources may be associated with the firstresources. The wireless device may send the sidelink transmission viathe second resources using a transmission power. The transmission powermay be based on the received power of the one or more PSFCH resources.

Resource selection for communications (e.g., sidelink transmissions, andor any other type of communication) based on exclusion of resources maynot always be optimal. For example, excluding resources may result inresource shortage and/or increase latency. Various examples describedherein may use resource exclusion based on one or more considerations.For example, a priority of the communications may be considered fordetermining whether enhanced resource selection may be used. Asdescribed herein, one or more priority levels of a sidelink transmission(e.g., the sidelink transmission A and/or the sidelink transmission B,as described above) may be considered (e.g., used as a criteria) forimplementing the enhanced resource selection procedure (e.g., based onfeedback A measurement by a wireless device). Use of priority levels asdescribed herein may provide advantages such as reduced interference toother wireless devices, reduced processing latency for resourceselection, and/or improved robustness and/or link quality of wirelessdevice transmissions (e.g., sidelink transmissions).

Returning to FIG. 24, an enhanced resource selection that may beperformed/used by a wireless device (e.g., wireless device 2430) may beimproved by using one or more priorities. For example, a resourceselection mechanism may account for a one or more priorities, such as afirst priority level of the sidelink transmission A and a secondpriority level of wireless device 2430's sidelink transmission B.Implementing the enhanced resource selection procedure for selectingnon-overlapped resources by wireless device 2430 may increase aprocessing latency for selecting the third resources for the sidelinktransmission B. Increased processing latency for selecting the thirdresources for the sidelink transmission B may be disadvantageous, forexample, if the second priority level of the sidelink transmission B isgreater than the first priority level of the sidelink transmission A.Implementing the enhanced resource selection procedure for reducing thepower for sending the sidelink transmission B by wireless device 2430may decrease robustness and link quality of the sidelink transmission B.Various examples herein use priority levels of the sidelink transmissionA and/or the sidelink transmission B for implementing the enhancedresource selection procedure (e.g., based on feedback A measurement) bya wireless device. Use of priority levels may reduce the interferencefrom the wireless device to other wireless devices, reduce theprocessing latency for selecting resources for the sidelink transmissionB, and/or improve the robustness and/or the link quality of the sidelinktransmission B.

For example, the wireless device 2430 may exclude the second resourcesfrom a candidate resource set based on the first priority level of thesidelink transmission A and the feedback A measurement. The wirelessdevice 2430 may determine a threshold value based on the first prioritylevel and/or the second priority level of the sidelink transmission B.The wireless device 2430 may exclude the second resources from thecandidate resource set, for example, if the feedback A measurementindicates that a received power of the feedback A is greater than thethreshold value. The wireless device 2430 may exclude the secondresources from the candidate resource set, for example, based on an RSRPof the sidelink transmission A being greater than an RSRP thresholdvalue and/or a received power of the feedback A being greater than athreshold value. The wireless device 2430 may exclude the secondresources from the candidate resource set, for example, based on an RSRPthreshold. The wireless device 2430 may determine the RSRP threshold,for example, based on a received power of the feedback A. The wirelessdevice 2430 may exclude the second resources from the candidate resourceset, for example, if the sidelink transmission A measurement indicatesthat an RSRP of the first resources is greater than the RSRP threshold.The wireless device 2430 may determine a transmit power for sending thesidelink transmission B, via the third resources, based on the feedbackA measurement. The wireless device 2430 may send the sidelinktransmission B, via the third resources, using the transmit power. Anassociation mapping between a PSSCH and one or more PSFCH resources maybe used, such as described above.

FIG. 37 shows an example of an association mapping between PSSCH andPSFCH resources. The example association mapping may be based on sensingof a wireless device during a resource selection procedure. The mappingmay correspond to the mapping described with respect to FIG. 26, except,for example, the possible reserved resources by a sidelink transmissionmay differ. The possible reserved resources by a sidelink transmissionin FIG. 37, for example, may be in slot 2. Any slots may be used for thepossible reserved resources by a sidelink transmission.

FIG. 38 shows an example method for resource selection. The examplemethod 3800 may comprise PSFCH-based exclusion of resources. At step3810, a wireless device may trigger a resource selection procedure forselecting resources for a first sidelink transmission. The wirelessdevice may trigger the resource selection procedure, for example, basedon (e.g., after or in response to) determining that there are not enoughavailable resources at the wireless device for sending the firstsidelink transmission. The wireless device may trigger the resourceselection procedure, for example, based on a counter for counting aquantity of transmissions. The wireless device may set the counter equalto a first value (e.g., an initial value). The counter may be decreasedby one based on (e.g., after) each transmission. The wireless device maytrigger the resource selection procedure (e.g., with a probability), forexample, if a value of the counter equals zero (or any other value). Thewireless device may have selected one or more resources for the firstsidelink transmission. The wireless device may determine a resourcecollision via the selected one or more resources. The wireless devicemay trigger the resource selection procedure for re-selecting resources,for example, based on (e.g., after or in response to) determining thecollision. Steps 3820 and 3830 in FIG. 38 may correspond to steps 2720and 2730 described with respect to FIG. 27.

At step 3846 a, the wireless device may receive a second sidelinktransmission, via first resources, in the sensing window. The secondsidelink transmission may comprise SCI and/or a TB. The SCI may indicatea priority of the second sidelink transmission. The SCI may indicate aresource assignment for second resources in the selection window. Thewireless device may send, via the second resources, the same TB asreceived in the second sidelink transmission. The SCI may indicate areservation period, of the one or more reservation periods, for resourcereservation of second resources in the selection window. The wirelessdevice may send, via the second resources, a different TB than the TBreceived in the second sidelink transmission. The priority may be aphysical layer priority of a packet in the second sidelink transmission.The priority may map to (or associate with) one or more logical channelpriorities (LCPs) of the second sidelink transmission.

At step 3846 b, the wireless device may determine one or more PSFCHresources in the sensing window. The one or more PSFCH resources may beassociated with the first resources, for example, based on anassociation mapping between a PSSCH of the second sidelink transmissionand the one or more PSFCH resources. The wireless device may determinethe one or more PSFCH resources based on a measurement of the one ormore PSFCH resources. The measurement may be based on an energydetection of the one or more PSFCH resources. The measurement maycomprise received power(s) of signals sent via the one or more PSFCHresources, RSRP(s) of signals sent via the one or more PSFCH resources,RSSIs of the one or more PSFCH resources, a RSRQs of the one or morePSFCH resources, and/or SINRs of the one or more PSFCH resources. Themeasurement may comprise received power(s) of signals sent via the oneor more PSFCH resources. For example, the received power(s) may compriseaverage or highest received power(s) of signals sent via the one or morePSFCH resources. For example, the received power(s) may comprise averageor highest received power(s) of one or more reference signals sent viathe one or more PSFCH resources. The wireless device mayassume/determine that a transmission power of signals sent via the oneor more PSFCH resources is a maximum transmission power (or any othertransmission power). The wireless device may compare the receivedpower(s) of signals sent via the one or more PSFCH resources with one ormore threshold values. The wireless device may determine the one or morePSFCH resources based on the measurement of the one or more PSFCHresources and the one or more threshold values. A base station may senda message to the wireless device for configuring one or more parameters.The one or more parameters may indicate the one or more thresholdvalues. The message may comprise an RRC message and/or SIB, a MAC CE,and/or DCI. A second wireless device may send a message to the wirelessdevice for configuring the one or more threshold values. The message maycomprise a sidelink RRC message, a sidelink MAC CE, and/or SCI. The oneor more threshold values may be pre-configured for the wireless device.A memory associated with the wireless device may store the one or morethreshold values.

At step 3846 c, the wireless device may exclude the second resourcesfrom the candidate resource set, for example, based on the measurementof the one or more PSFCH resources associated with first resources. Thewireless device may exclude the second resources from the candidateresource set, for example, further based on the priority of the secondsidelink transmission via the first resources and/or a priority of thefirst sidelink transmission. At step 3890, the wireless device mayselect third resources from the candidate resource set based on theexcluding the second resources from the candidate resource set. At step3891, the wireless device may send the first sidelink transmission viathe selected third resources.

FIG. 39 shows an example method for power control in a resourceselection procedure. The example method 3900 may comprise PSFCH-basedpower control. At step 3910, a wireless device may trigger a resourceselection procedure for selecting resources for a first sidelinktransmission. The wireless device may trigger the resource selectionprocedure, for example, based on (e.g., after or in response to)determining that there are not enough available resources at thewireless device for sending the first sidelink transmission. Thewireless device may trigger the resource selection procedure based on acounter for counting a quantity of transmissions. The wireless devicemay set the counter equal to a first value (e.g., an initial value). Thecounter may be decreased by one based on (e.g., after) eachtransmission. The wireless device may trigger the resource selectionprocedure (e.g., with a probability) if a value of the counter equalszero. The wireless device may have selected one or more resources forthe first sidelink transmission. The wireless device may determine aresource collision via the selected one or more resources. The wirelessdevice may trigger the resource selection procedure for re-selectingresources, for example, based on (e.g., after or in response to)determining the collision. Steps 3920 and 3930 in FIG. 39 may correspondto steps 2720 and 2730 described with respect to FIG. 27.

At step 3947 a, the wireless device may receive a second sidelinktransmission via first resources in the sensing window. The secondsidelink transmission may comprise SCI and a TB. The SCI may indicate apriority of the second sidelink transmission. The SCI may indicate aresource assignment for second resources in the selection window. Thewireless device may send, via the second resources the same TB asreceived in the second sidelink transmission. The SCI may indicate areservation period, of the one or more reservation periods, for resourcereservation of second resources in the selection window. The wirelessdevice may send, via the second resources, a different TB than the TBreceived in the second sidelink transmission. The priority may be aphysical layer priority of a packet in the second sidelink transmission.The priority may map to (or associate with) one or more LCPs of thesecond sidelink transmission.

At step 3947b, the wireless device may determine one or more PSFCHresources in the sensing window. The one or more PSFCH resources may beassociated with the first resources based on an association mappingbetween a PSSCH of the second sidelink transmission and the one or morePSFCH resources. The wireless device may determine the one or more PSFCHresources based on a measurement of the one or more PSFCH resources. Themeasurement may be based on an energy detection of the one or more PSFCHresources. The measurement may comprise received power(s) of signalssent via the one or more PSFCH resources, RSRPs of signals sent via theone or more PSFCH resources, RSSI(s) of signals sent via the one or morePSFCH resources, RSRQ(s) of signals sent via the one or more PSFCHresources, and/or SINR(s) of the one or more PSFCH resources. Themeasurement may comprise received power(s) of signals sent via the oneor more PSFCH resources. The received power(s) may comprise average orhighest received power(s) of signals sent via the one or more PSFCHresources. The received power(s) may comprise average or highestreceived power(s) of one or more reference signals sent via the one ormore PSFCH resources. The wireless device may assume/determine that atransmission power of signals sent via the one or more PSFCH resourcesis a maximum transmission power (or any other transmission power). Thewireless device may compare the received power(s) of signals sent viathe one or more PSFCH resources with one or more threshold values. Thewireless device may determine the one or more PSFCH resources based onthe measurement of the one or more PSFCH resources and the one or morethreshold values. A base station may send a message to the wirelessdevice for configuring one or more parameters. The one or moreparameters may indicate the one or more threshold values. The messagemay comprise an RRC message and/or SIB, a MAC CE, and/or DCI. A secondwireless device may send a message to the wireless device forconfiguring the one or more threshold values. The message may comprise asidelink RRC message, a sidelink MAC CE, and/or SCI. The one or morethreshold values may be pre-configured for the wireless device. A memoryof the wireless device may store the one or more threshold values.

At step 3947 c, the wireless device may send the first sidelinktransmission via the second resources. The wireless device may send thefirst sidelink transmission using a transmission power. The wirelessdevice may determine the transmission power based on the measurement ofthe one or more PSFCH resources. The wireless device may determine thetransmission power further based on the priority of the second sidelinktransmission via the first resources and/or a priority of the firstsidelink transmission.

FIG. 40 shows an example resource selection for interference reduction.The example resource selection may be based on a feedback measurementand a sidelink measurement. A wireless device 4010 may send, via firstresources, sidelink transmission A to a wireless device 4020. Thewireless device 4020 may send feedback A to the wireless device 4010,for example, based on (e.g., after or in response to) receiving thesidelink transmission A. The wireless device 4030 may trigger theresource selection procedure to select third resources from a candidateresource set. The third resources may be for sending a sidelinktransmission.

The wireless device 4030 may receive, from the wireless device 4010, thesidelink transmission A in a sensing window. The wireless device 4030may measure an RSRP of the sidelink transmission A. The wireless device4030 may measure an RSRP based on SCI of the sidelink transmission A.The SCI may indicate a priority of the sidelink transmission A. Amapping between one or more RSRP threshold values and one or morepriorities may be configured. A first priority of the one or morepriorities may map to (or associate with) a first RSRP threshold valueof the one or more RSRP threshold values. A second priority of the oneor more priorities may map to (or associate with) a second RSRPthreshold value of the one or more RSRP threshold values. The wirelessdevice 4030 may determine an RSRP threshold value based on the priorityof the sidelink transmission A and/or based on the mapping between oneor more RSRP threshold values and one or more priorities. The wirelessdevice 4030 may determine a distance A from the wireless device 4030based on the RSRP threshold value. A base station may send a message, tothe wireless device 4030, for configuring/determining the RSRP thresholdvalue. The message may comprise an RRC message, a MAC CE, and/or DCI. Awireless device may send a message, to the wireless device 4030, forconfiguring/determining the RSRP threshold value. The message maycomprise SCI. The RSRP threshold value may be pre-configured. A memoryassociated with the wireless device 4030 may store the pre-configuredRSRP threshold value. The wireless device 4030 may determine the thirdresources, for example, based on the RSRP of the sidelink transmission Aand the RSRP threshold value.

The wireless device 4030 may receive, from the wireless device 4020, thefeedback A in the sensing window. The feedback A may be received viaPSFCH resources. The wireless device 4030 may measure the feedback Abased on a received power of the feedback A. The PSFCH resources may beassociated with the first resources for sending the sidelinktransmission A. The wireless device 4030 may determine a distance B fromthe wireless device 4030, for example, based on a received powerthreshold value. A base station may send a message, to the wirelessdevice 4030, for configuring/determining the received power thresholdvalue. The message may comprise an RRC message, a MAC CE, and/or DCI. Awireless device may send a message, to the wireless device 4030, forconfiguring/determining the received power threshold value. The messagemay comprise SCI. The received power threshold value may bepre-configured. A memory associated with the wireless device 4030 maystore the pre-configured received power threshold value. The wirelessdevice 4030 may determine the third resources, for example, based on thereceived power of the feedback A and the received power threshold value.

The wireless device 4030 may determine second resources based on the SCIof the sidelink transmission A. The SCI may indicate resource assignmentof the second resources for a future sidelink transmission, via aresource pool, from the wireless device 4010 to the wireless device4020. The future sidelink transmission may be a retransmission of thesame TB as sent in the sidelink transmission A. The SCI may indicate areservation period, of one or more reservation periods, for resourcereservation of the second resources. The second resources may be for afuture sidelink transmission from the wireless device 4010, via aresource pool, to the wireless device 4020. The future sidelinktransmission may be a new transmission of a different TB than a TB sentin the sidelink transmission A. For example, a base station may send, tothe wireless device 4030, a message for configuring the one or morereservation periods of the resource pool. The resource pool may comprisethe first resources, the second resources, the third resources, and thePSFCH resources. The message may comprise an RRC message, a MAC CE,and/or DCI. For example, the one or more reservation periods of theresource pool may be pre-configured for the wireless device 4030. Amemory associated with the wireless device 4030 may store the one ormore reservation periods of the resource pool.

The wireless device 4030 may exclude the second resources from thecandidate resource set based on one or more considerations. The wirelessdevice 4030 may exclude the second resources from the candidate resourceset, for example, if the RSRP of the sidelink transmission A is greaterthan the RSRP threshold value and/or the received power of the feedbackA is greater than the received power threshold value. The wirelessdevice 4030 may determine that a distance from the wireless device 4030to the wireless device 4010 is smaller than the distance A and adistance from the wireless device 4030 to the wireless device 4020 issmaller than the distance B, for example, based on the RSRP of thesidelink transmission A being greater than the RSRP threshold valueand/or the received power of the feedback A being greater than thereceived power threshold value. The wireless device 4030 may not excludethe second resources from the candidate resource set, if the RSRP of thesidelink transmission A is less than the RSRP threshold value and/or thereceived power of the feedback A is less than the received powerthreshold value. The wireless device 4030 may determine that a distancefrom the wireless device 4030 to the wireless device 4010 is larger thanthe distance A and a distance from the wireless device 4030 to thewireless device 4020 is larger than the distance B, for example, basedon the RSRP of the sidelink transmission A being less than the RSRPthreshold value and the received power of the feedback A being less thanthe received power threshold value.

The wireless device 4030 may determine the threshold value. The wirelessdevice may determine the threshold value, for example, based on a firstpriority of the sidelink transmission A and/or based on and a mappingbetween one or more RSRP threshold values and one or more priorities.The mapping may map the threshold value of the one or more RSRPthreshold values to the first priority of the one or more priorities.The wireless device 4030 may determine the threshold value based on asecond priority of wireless device 4030's sidelink transmission and/orbased on a mapping between one or more RSRP threshold values and one ormore priorities. The mapping may map the threshold value of the one ormore RSRP threshold values to the second priority of the one or morepriorities. The wireless device 4030 may determine the threshold valuebased on a first priority of the sidelink transmission A, a secondpriority of wireless device 4030′s sidelink transmission, and/or amapping between one or more RSRP threshold values and one or morepriorities. The mapping may map the threshold value of the one or moreRSRP threshold values to a combination of the first priority and thesecond priority of the one or more priorities. For example, thecombination of the first priority and the second priority may correspondto a summation operation of the first priority and the second priority.The wireless device 4030 may select the third resources from thecandidate resource set based on the excluding the second resources fromthe candidate resource set.

The wireless device 4030 may determine one or more distances from thewireless device 4030, for example, based on one or more received powerthreshold values. The wireless device 4030 may determine the thirdresources based on the received power of the feedback A, the one or morereceived power threshold values, and/or a condition. The condition maybe a probability for excluding the second resources from the candidateresource set, corresponding to the one or more received power thresholdvalues. The wireless device 4030 may compare the received power of thefeedback A EA with a first received power threshold value Th1 and asecond received power threshold value Th2, where Th1 <Th2. The wirelessdevice 4030 may determine a probability P1 for excluding the secondresources from the candidate resource set, for example, if EA ≤Th1. Thewireless device 4030 may determine a probability P2 for excluding thesecond resources from the candidate resource set, for example, if Th1<EA <Th2. The wireless device 4030 may determine a probability P3 forexcluding the second resources from the candidate resource set, forexample, if Th2 ≤EA. In an example, 1≥P3 ≥P2 ≥P1 ≥0.

FIG. 41 shows an example method of resource selection. The examplemethod 4100 may be based on a PSFCH-based exclusion. One or moreresources may be excluded based on priorities of sidelink transmissions.Referring to FIG. 41, and at step 4110, a wireless device may trigger aresource selection procedure for selecting resources for a firstsidelink transmission. At step 4120, the wireless device may determine asensing window based on the resource selection procedure, a selectionwindow based on the triggering the resource selection procedure, and/orone or more reservation periods for resource reservation. At step 4130,the wireless device may initialize a candidate resource set. Thecandidate resource set may comprise a plurality of candidate resources.

At step 4148 a, the wireless device may receive a second sidelinktransmission via first resources in the sensing window. The secondsidelink transmission may comprise SCI and a TB. The SCI may indicate apriority of the second sidelink transmission. The SCI may indicate aresource assignment for second resources in the selection window. Thewireless device may send, via the second resources, the same TB asreceived in the second sidelink transmission. The SCI may indicate areservation period, of the one or more reservation periods, for resourcereservation of second resources in the selection window. The wirelessdevice may send, via the second resources, a different TB than the TBreceived in the second sidelink transmission. The priority may be aphysical layer priority of a packet in the second sidelink transmission.The priority may map to (or associate with) one or more LCPs of thesecond sidelink transmission. The wireless device may measure an RSRP ofthe second sidelink transmission based on the SCI. The wireless devicemay compare the RSRP of the second sidelink transmission with an RSRPthreshold value. A mapping between one or more RSRP threshold values andone or more priorities may be configured. A first priority of the one ormore priorities may map to (or associate with) a first RSRP thresholdvalue of the one or more RSRP threshold values. A second priority of theone or more priorities may map to (or associate with) a second RSRPthreshold value of the one or more RSRP threshold values. The wirelessdevice may determine the RSRP threshold value, for example, based on thepriority of the second sidelink transmission and the mapping between oneor more RSRP threshold values and one or more priorities. The mappingmay map/associate the RSRP threshold value to the priority of the secondsidelink transmission. The wireless device may determine the RSRPthreshold value, for example, based on a priority of the first sidelinktransmission and the mapping between one or more RSRP threshold valuesand one or more priorities. The mapping may map/associate the RSRPthreshold value to the priority of the first sidelink transmission. Thewireless device may determine the RSRP threshold value, for example,based on the priority of the second sidelink transmission, a priority ofthe first sidelink transmission, and the mapping between one or moreRSRP threshold values and one or more priorities. The mapping maymap/associate the RSRP threshold value to a combination of the priorityof the first sidelink transmission and the priority of the secondsidelink transmission. For example, the combination may be an arithmetic(e.g., addition and/or subtraction) operation of the priority of thefirst sidelink transmission and the priority of the second sidelinktransmission. A base station may send a message, to the wireless device,configuring the mapping. The message may comprise an RRC message, a MACCE, and/or DCI. A third wireless device may send a message, to thewireless device, for configuring the mapping. The message may compriseSCI. The mapping may be pre-configured. A memory associated with thewireless device may store the pre-configured mapping.

At step 4148 b, the wireless device may determine one or more PSFCHresources in the sensing window. The one or more PSFCH resources may beassociated with the first resources, for example, based on anassociation mapping between a PSSCH of the second sidelink transmissionand the one or more PSFCH resources. The wireless device may determinethe one or more PSFCH resources based on a measurement of the one ormore PSFCH resources. The measurement may be based on an energydetection of the one or more PSFCH resources. The measurement maycomprise received power(s) of signals sent via the one or more PSFCHresources, RSRP(s) of signals sent via the one or more PSFCH resources,RSSI(s) of the one or more PSFCH resources, RSRQ(s) of the one or morePSFCH resources, and/or SINR(s) of the one or more PSFCH resources. Themeasurement may comprise received power(s) of signals sent via the oneor more PSFCH resources. For example, the received power may compriseaverage or highest received power(s) of signals sent via the one or morePSFCH resources. For example, the received power may comprise average orhighest received power(s) of one or more reference signals sent via theone or more PSFCH resources. The wireless device may assume/determinethat a transmission power of signals sent via the one or more PSFCHresources is a maximum transmission power (or any other transmissionpower).

At step 4148 c, the wireless device may determine a threshold valuebased on the priority of the second sidelink transmission via the firstresources and/or the priority of the first sidelink transmission. Amapping between one or more threshold values and one or more prioritiesmay be configured/determined. A first priority of the one or morepriorities may map to (or associate with) a first threshold value of theone or more threshold values. A second priority of the one or morepriorities may map to (or associate with) a second threshold value ofthe one or more threshold values. The wireless device may determine thethreshold value based on the priority of the second sidelinktransmission and the mapping between one or more threshold values andone or more priorities. The mapping may map/associated the thresholdvalue to the priority of the second sidelink transmission. The wirelessdevice may determine the threshold value based on the priority of thefirst sidelink transmission and the mapping between one or morethreshold values and one or more priorities. The mapping maymap/associate the threshold value to the priority of the first sidelinktransmission. The wireless device may determine the threshold valuebased on the priority of the second sidelink transmission, the priorityof the first sidelink transmission, and the mapping between one or morethreshold values and one or more priorities. The mapping maymap/associate the threshold value to a combination of the priority ofthe first sidelink transmission and the priority of the second sidelinktransmission. The combination may be an arithmetic (e.g., additionand/or subtraction) operation comprising the priority of the firstsidelink transmission and the priority of the second sidelinktransmission. A base station may send a message, to the wireless device,configuring the mapping. The message may comprise an RRC message, a MACCE, and/or DCI. A third wireless device may send a message, to thewireless device, for configuring the mapping. The message may compriseSCI. The mapping may be pre-configured. A memory of the wireless devicemay store the pre-configured mapping.

At step 4148 d, the wireless device may exclude the second resourcesfrom the candidate resource set. The wireless device may exclude thesecond resources from the candidate resource set, for example, based onthe measurement of the one or more PSFCH resources associated with firstresources. The wireless device may exclude the second resources from thecandidate resource set, for example, if a received power of the one ormore PSFCH resources is greater than the threshold value. At step 4190,the wireless device may select third resources from the candidateresource set. The wireless device may select third resources, forexample, based on the excluding the second resources from the candidateresource set. At step 4191, the wireless device may send the firstsidelink transmission via the selected third resources.

The wireless device may perform PSFCH-based exclusion 4148 describedwith respect to FIG. 41, for example, after a second exclusion 2250 suchas described with respect to FIG. 22. The wireless device may performPSFCH-based exclusion 4148 described with respect to FIG. 41, forexample, within a second exclusion 2250 such as described with respectto FIG. 22 (e.g., as part of the second exclusion 2250).

FIG. 42 shows an example method for determination of transmission power.The example method 4200 may comprise PSFCH-based power control in aresource selection procedure. A first sidelink transmission may be sentvia a second resource with a determined transmission power. At step4210, a wireless device may trigger a resource selection procedure forselecting resources for a first sidelink transmission. At step 4220, thewireless device may determine a sensing window based on the triggeringthe resource selection procedure. The wireless device may determine aselection window based on the triggering the resource selectionprocedure. The wireless device may determine one or more reservationperiods for resource reservation. At step 4230, the wireless device mayinitialize a candidate resource set. The candidate resource set maycomprise a plurality of candidate resources.

At step 4249 a, the wireless device may receive, via first resources, asecond sidelink transmission in the sensing window. The second sidelinktransmission may comprise SCI and a TB. The SCI may indicate a priorityof the second sidelink transmission. The SCI may indicate a resourceassignment for second resources in the selection window. The wirelessdevice may send, via the second resources, the same TB as received inthe second sidelink transmission. The SCI may indicate a reservationperiod, of the one or more reservation periods, for resource reservationof second resources in the selection window. The wireless device maysend, via the second resources, a different TB than the TB received inthe second sidelink transmission. The priority may be a physical layerpriority of a packet in the second sidelink transmission. The prioritymay map to (or associate with) one or more LCPs of the second sidelinktransmission. The wireless device may measure an RSRP of the secondsidelink transmission, for example, based on the SCI. The wirelessdevice may compare the RSRP of the second sidelink transmission with anRSRP threshold value. A mapping between one or more RSRP thresholdvalues and one or more priorities may be configured/determined. A firstpriority of the one or more priorities may map to (or associate with) afirst RSRP threshold value of the one or more RSRP threshold values. Asecond priority of the one or more priorities may map to (or associatewith) a second RSRP threshold value of the one or more RSRP thresholdvalues. The wireless device may determine the RSRP threshold value, forexample, based on the priority of the second sidelink transmission, andthe mapping between one or more RSRP threshold values and one or morepriorities. The mapping may map/associate the RSRP threshold value tothe priority of the second sidelink transmission. The wireless devicemay determine the RSRP threshold value, for example, based on a priorityof the first sidelink transmission, and the mapping between one or moreRSRP threshold values and one or more priorities. The mapping maymap/associate the RSRP threshold value to the priority of the firstsidelink transmission. The wireless device may determine the RSRPthreshold value based on the priority of the second sidelinktransmission, a priority of the first sidelink transmission, and themapping between one or more RSRP threshold values and one or morepriorities. The mapping may map/associate the RSRP threshold value to acombination of the priority of the first sidelink transmission and thepriority of the second sidelink transmission. For example, thecombination may be an arithmetic (e.g., addition and/or subtraction)operation (or any other mathematical or logical operation) of thepriority of the first sidelink transmission and the priority of thesecond sidelink transmission. A base station may send a message, to thewireless device, configuring the mapping. The message may comprise anRRC message, a MAC CE, and/or DCI. A third wireless device may send amessage, to the wireless device, for configuring the mapping. Themessage may comprise SCI. The mapping may be pre-configured. A memory ofthe wireless device may store the pre-configured mapping.

As shown in step 4249b, the wireless device may determine one or morePSFCH resources in the sensing window. The one or more PSFCH resourcesmay be associated with the first resources, for example, based on anassociation mapping between a PSSCH of the second sidelink transmissionand the one or more PSFCH resources. The wireless device may determinethe one or more PSFCH resources based on a measurement of the one ormore PSFCH resources. The measurement may be based on an energydetection of the one or more PSFCH resources. The measurement maycomprise received power(s) of signals sent via the one or more PSFCHresources, RSRP(s) of signals sent via the one or more PSFCH resources,RSSI(s) of the one or more PSFCH resources, RSRQ(s) of the one or morePSFCH resources, and/or SINR(s) of the one or more PSFCH resources. Themeasurement may comprise received power(s) of signals sent via of theone or more PSFCH resources. For example, the received power(s) may beaverage or highest received power(s) of signals sent via the one or morePSFCH resources. For example, the received power(s) may be average orhighest received power(s) of one or more reference signals sent via theone or more PSFCH resources. The wireless device may assume/determinethat a transmission power of signals sent via the one or more PSFCHresources is a maximum transmission power (or any other transmissionpower).

As shown in step 4249 c, the wireless device may determine a thresholdvalue, for example, based on the priority of the second sidelinktransmission via the first resources and/or the priority of the firstsidelink transmission. A mapping between one or more threshold valuesand one or more priorities may be configured/determined. For example, afirst priority of the one or more priorities may map to (or associatewith) a first threshold value of the one or more threshold values. Asecond priority of the one or more priorities may map to (or associatewith) a second threshold value of the one or more threshold values. Thewireless device may determine the threshold value, for example, based onthe priority of the second sidelink transmission, and the mappingbetween one or more threshold values and one or more priorities. Themapping may map/associate the threshold value to the priority of thesecond sidelink transmission. The wireless device may determine thethreshold value, for example, based on the priority of the firstsidelink transmission, and the mapping between one or more thresholdvalues and one or more priorities. The mapping may map/associate thethreshold value to the priority of the first sidelink transmission. Thewireless device may determine the threshold value based on the priorityof the second sidelink transmission, the priority of the first sidelinktransmission, and the mapping between one or more threshold values andone or more priorities. The mapping may map/associate the thresholdvalue to a combination of the priority of the first sidelinktransmission and the priority of the second sidelink transmission. Forexample, the combination may be an arithmetic (e.g., addition and/orsubtraction) operation of the priority of the first sidelinktransmission and the priority of the second sidelink transmission. Abase station may send a message, to the wireless device, configuring themapping. The message may comprise an RRC message, a MAC CE, and/or DCI.A third wireless device may send a message, to the wireless device, forconfiguring the mapping. The message may comprise a SCI. The mapping maybe pre-configured. A memory of the wireless device may store thepre-configured mapping.

As shown in step 4249 d, the wireless device may send the first sidelinktransmission via the second resources. The wireless device may send thefirst sidelink transmission using a transmission power. The wirelessdevice may determine the transmission power, for example, based on themeasurement of the one or more PSFCH resources. The wireless device maydetermine a first transmission power for sending the first sidelinktransmission, for example, based on a received power of (e.g., receivedpower of signals sent via) the one or more PSFCH resources is greaterthan a threshold value of the one or more threshold values. The wirelessdevice may determine a second transmission power for sending the firstsidelink transmission, for example, based on the received power of(e.g., received power of signals sent via) the one or more PSFCHresources being less than the threshold value of the one or morethreshold values. The first transmission power may be less than thesecond transmission power.

FIG. 43A, FIG. 43B, and FIG. 43C show examples of mapping between one ormore threshold values and one or more priorities. A wireless device maytrigger a resource selection procedure for sending a first sidelinktransmission. The first sidelink transmission may have a priority Pi.The wireless device may receive a second sidelink transmission, viaresources, in a sensing window. SCI of the second sidelink transmissionmay indicate a priority Pj of the second sidelink transmission. As shownin FIG. 43A, the wireless device may determine one or more thresholdvalues, for example, based on the priority Pi of the first sidelinktransmission. As shown in FIG. 43A, there may be n threshold values(e.g., Th1(Pi), Th2(Pi), Th3(Pi), Th4(Pi), and Thn(Pi)). The n thresholdvalues may vary based on the priority Pi. The wireless device maydetermine probability for excluding the resources from a candidateresource set based on the one or more threshold values. The wirelessdevice may determine the probability 3 (e.g., Pro3 in FIG. 43A), forexample, if a received power Prx of PSFCH resources (e.g., signals sentvia PSFCH resources) associated with the second sidelink transmissionsatisfies the condition Th2 (Pi) <Prx ≤Th3 (Pi). As shown in FIG. 43B,the wireless device may determine one or more threshold values based onthe priority Pj of the second sidelink transmission. As shown in FIG.43B, there may be n threshold values (e.g., Th1(Pj), Th2(Pj), Th3(Pj),Th4(Pj),and Thn(Pj)). The n threshold values may vary based on thepriority Pj. The wireless device may determine probability for excludingthe resources from a candidate resource set based on the one or morethreshold values. The wireless device may determine the probability 3(e.g., Pro3 in FIG. 43B), for example, if a received power Prx of PSFCHresources (e.g., signals sent via PSFCH resources) associated with thesecond sidelink transmission satisfies Th2(Pj) <Prx ≤Th3(Pj). As shownin FIG. 43C, the wireless device may determine one or more thresholdvalues based on a combination of the priority Pi of the first sidelinktransmission and the priority Pj of the second sidelink transmission.For example, the combination may be an arithmetic (e.g., addition and/orsubtraction) operation (or any other operation) based on the priority Piand the priority Pj. As shown in FIG. 43C, there may be n thresholdvalues (e.g., Th1(Pi,Pj), Th2(Pi,Pj), Th3(Pi, Pj), Th4(Pi, Pj), andThn(Pi, Pj)). The n threshold values may vary based on the priority Piand the priority Pj. The wireless device may determine probability forexcluding the resources from a candidate resource set based on the oneor more threshold values. The wireless device may determine theprobability 3 (e.g., Pro3 in FIG. 43C), for example, if a received powerPrx of PSFCH resources (e.g., signals sent via PSFCH resources)associated with the second sidelink transmission satisfies Th2(Pi, Pj)<Prx ≤Th3 (Pi, Pj).

FIG. 44 shows an example resource selection for interference reduction.The example resource selection may be based on feedback measurement andsidelink measurement. An offset value to be used for resource exclusionmay be calculated based on signal powers (e.g., RSRP) of sidelink A andfeedback A. A wireless device 4410 may send, via first resources,sidelink transmission A to wireless device 4420. The wireless device4420 may send feedback A to the wireless device 4410, for example, basedon receiving the sidelink transmission A. A wireless device 4430 maytrigger the resource selection procedure to select third resources froma candidate resource set. The third resource may be for sending asidelink transmission by the wireless device 4430.

The wireless device 4430 may receive, from the wireless device 4410, thesidelink transmission A in a sensing window. The wireless device 4430may measure an RSRP of the sidelink transmission A, for example, basedon SCI of the sidelink transmission A. The SCI may indicate a priorityof the sidelink transmission A. A mapping between one or more RSRPthreshold values and one or more priorities may be configured. A firstpriority of the one or more priorities may map to (or associate with) afirst RSRP threshold value of the one or more RSRP threshold values. Asecond priority of the one or more priorities may map to (or associatewith) a second RSRP threshold value of the one or more RSRP thresholdvalues. The wireless device 4430 may determine an RSRP threshold value,for example, based on the priority of the sidelink transmission A, andthe mapping between one or more RSRP threshold values and one or morepriorities. A base station may send a message, to the wireless device4430, for configuring/determining the RSRP threshold value. The messagemay comprise an RRC message, a MAC CE, and/or DCI. A wireless device maysend a message for configuring/determining the RSRP threshold value tothe wireless device 4430. The message may comprise SCI. The RSRPthreshold value may be pre-configured. A memory of the wireless device4430 may store the pre-configured RSRP threshold value. The wirelessdevice 4430 may determine the third resources based on the RSRP of thesidelink transmission A and the RSRP threshold value.

The wireless device 4430 may receive the feedback A, from the wirelessdevice 4420, in the sensing window. The wireless device 4430 may receivethe feedback A via PSFCH resources. The wireless device 4430 may measurethe feedback A based on a received power of the feedback A. The PSFCHresources may be associated with the first resources used for sendingthe sidelink transmission A. The wireless device 4430 may determine anoffset value based on a threshold value. A mapping between one or morethreshold values and one or more priorities may beconfigured/determined. A first priority of the one or more prioritiesmay map to (or associate with) a first threshold value of the one ormore threshold values. A second priority of the one or more prioritiesmay map to (or associate with) a second threshold value of the one ormore threshold values. The wireless device 4430 may determine thethreshold value, for example, based on the priority of the sidelinktransmission A, and the mapping between one or more threshold values andone or more priorities. A base station may send, to the wireless device4430, a message configuring/determining the mapping. The message maycomprise an RRC message, a MAC CE, and/or DCI. A wireless device maysend, to the wireless device 4430, a message for configuring/determiningthe mapping. The message may comprise SCI. The mapping may bepre-configured. A memory associated with the wireless device 4430 maystore the pre-configured mapping. The wireless device 4430 may determinethe third resources, for example, based on the received power of thefeedback A and the mapping.

The wireless device 4430 may determine second resources based on the SCIof the sidelink transmission A. The SCI may indicate resourceassignment, of the second resources, for a future sidelink transmission.The future sidelink transmission may be from the wireless device 4410 tothe wireless device 4420 via a resource pool. The future sidelinktransmission may be a retransmission of the same TB as sent in thesidelink transmission A. The SCI may indicate a reservation period, ofone or more reservation periods, for resource reservation of the secondresources for a future sidelink transmission (e.g., from the wirelessdevice 4410 to the wireless device 4420 of via a resource pool). Thefuture sidelink transmission may be a new transmission of a different TBthan than TB sent in the sidelink transmission A. A base station maysend a message for configuring/determining the one or more reservationperiods of the resource pool to the wireless device 4430. The resourcepool may comprise the first resources, the second resources, the thirdresources, and the PSFCH resources. The message may comprise an RRCmessage, a MAC CE, and/or DCI. The one or more reservation periods ofthe resource pool may be pre-configured for the wireless device 4430. Amemory associated with the wireless device 4430 may store the one ormore reservation periods of the resource pool.

The wireless device 4430 may exclude the second resources from thecandidate resource set. The wireless device 4430 may exclude the secondresources from the candidate resource set, for example, based on theRSRP of the sidelink transmission A, the RSRP threshold value, and/orthe offset value. The wireless device 4430 may determine a distance A′based on the RSRP of the sidelink transmission A, the RSRP thresholdvalue, and/or the offset value. The offset value may be added to theRSRP of the sidelink transmission A. The wireless device 4430 mayexclude the second resources from the candidate resource set, forexample, if (the RSRP of the sidelink A +the offset value) >the RSRPthreshold value. The wireless device 4430 may not exclude the secondresources from the candidate resource set, for example, if (the RSRP ofthe sidelink A +the offset value) <the RSRP threshold value. The offsetvalue may be added to the RSRP threshold value. The wireless device 4430may exclude the second resources from the candidate resource set, forexample, if the RSRP of the sidelink A >(the RSRP threshold value+theoffset value). The wireless device 4430 may not exclude the secondresources from the candidate resource set, for example, if the RSRP ofthe sidelink A<(the RSRP threshold value +the offset value). Thewireless device 4430 may select the third resources from the candidateresource set based on the excluding the second resources from thecandidate resource set.

The wireless device 4430 may determine one or more offset values, forexample, based on one or more threshold values. The wireless device 4430may determine the third resources based on the one or more offsetvalues. The wireless device 4430 may compare the received power of thefeedback A EA with a first threshold value Th1 and a second thresholdvalue Th2, where Th1 <Th2 The wireless device 4430 may determine a firstoffset value of the one or more offset values for excluding the secondresources from the candidate resource set, for example, if EA ≤Th1. Thewireless device 4430 may determine a second offset value of the one ormore offset values for excluding the second resources from the candidateresource set, for example, if Th1 <EA <Th2. The wireless device 4430 maydetermine a third offset value of the one or more offset values forexcluding the second resources from the candidate resource set, forexample, if Th2 ≤EA.

FIG. 45 shows an example method for resource selection. The examplemethod 4500 may comprise PSFCH-based resource exclusion based on an RSRPthreshold value and an offset value. At step 4510, a wireless device maytrigger a resource selection procedure for selecting resources for afirst sidelink transmission. At step 4520, the wireless device maydetermine a sensing window based on the triggering the resourceselection procedure. The wireless device may determine a selectionwindow based on the triggering the resource selection procedure. Thewireless device may determine one or more reservation periods forresource reservation. At step 4530, the wireless device may initialize acandidate resource set. The candidate resource set may comprise aplurality of candidate resources.

At step 4551 a, the wireless device may receive, via first resources, asecond sidelink transmission in the sensing window. The second sidelinktransmission may comprise SCI and a TB. The SCI may indicate a priorityof the second sidelink transmission. The SCI may indicate a resourceassignment for second resources in the selection window. The wirelessdevice may send, via the second resources, the same TB as included inthe second sidelink transmission. The SCI may further indicate areservation period, of the one or more reservation periods, for resourcereservation of second resources in the selection window. The wirelessdevice may send, via the second resources, a different TB than the TBincluded in the second sidelink transmission. The priority may be aphysical layer priority of a packet in the second sidelink transmission.The priority may map to (or associate with) one or more LCPs of thesecond sidelink transmission. The wireless device may measure an RSRP ofthe second sidelink transmission, for example, based on the SCI. Thewireless device may determine an RSRP threshold value based on a mappingbetween one or more RSRP threshold values and one or more priorities.For example, a first priority of the one or more priorities may map to(or associate with) a first RSRP threshold value of the one or more RSRPthreshold values. A second priority of the one or more priorities maymap to (or associate with) a second RSRP threshold value of the one ormore RSRP threshold values. The wireless device may determine the RSRPthreshold value, for example, based on the priority of the secondsidelink transmission, and/or the mapping between one or more RSRPthreshold values and one or more priorities. The mapping maymap/associate the RSRP threshold value to the priority of the secondsidelink transmission. The wireless device may determine the RSRPthreshold value, for example, based on a priority of the first sidelinktransmission, and/or the mapping between one or more RSRP thresholdvalues and one or more priorities. The mapping may map/associate theRSRP threshold value to the priority of the first sidelink transmission.The wireless device may determine the RSRP threshold value, for example,based on the priority of the second sidelink transmission, a priority ofthe first sidelink transmission, and/or the mapping between one or moreRSRP threshold values and one or more priorities. The mapping maymap/associate the RSRP threshold value to a combination of the priorityof the first sidelink transmission and the priority of the secondsidelink transmission. For example, the combination may be an arithmetic(e.g., addition and/or subtraction) operation (or any other operation)comprising the priority of the first sidelink transmission and thepriority of the second sidelink transmission. A base station may send amessage, to the wireless device, configuring the mapping. The messagemay comprise an RRC message, a MAC CE, and/or DCI. A third wirelessdevice may send a message, to the wireless device, for configuring themapping. The message may comprise SCI. The mapping may bepre-configured. A memory associated with the wireless device may storethe pre-configured mapping.

At step 4551 b, the wireless device may determine one or more PSFCHresources in the sensing window. The one or more PSFCH resources may beassociated with the first resources, for example, based on anassociation mapping between a PSSCH of the second sidelink transmissionand the one or more PSFCH resources. The wireless device may determinethe one or more PSFCH resources, for example, based on a measurement ofthe one or more PSFCH resources. The measurement may be based on anenergy detection of the one or more PSFCH resources. The measurement maycomprise received power(s) of signals sent via the one or more PSFCHresources, RSRP(s) of signals sent via the one or more PSFCH resources,RSSI(s) of the one or more PSFCH resources, RSRQ(s) of the one or morePSFCH resources, and/or SINR(s) of the one or more PSFCH resources. Themeasurement may comprise received power(s) of signals sent via the oneor more PSFCH resources. For example, the received power(s) may compriseaverage or highest received power(s) of signals sent via the one or morePSFCH resources. For example, the received power may comprise average orhighest received power(s) of one or more reference signals sent via theone or more PSFCH resources. The wireless device may assume/determinethat a transmission power of signals sent via the one or more PSFCHresources is a maximum transmission power.

At step 4551 c, the wireless device may determine an offset value. Thewireless device may determine the offset value, for example, based onthe measurement of one or more PSFCH resources in the sensing window, aset of threshold values, the priority of the first sidelinktransmission, and/or the priority of the second sidelink transmission.The set of threshold values may comprise one or more threshold values.The wireless device may determine the one or more threshold values, forexample, based on the priority of the second sidelink transmission viathe first resources and/or the priority of the first sidelinktransmission, and a mapping between one or more sets of threshold valuesand one or more priorities. A first priority of the one or morepriorities may map to (or associate with) a first set of thresholdvalues of the one or more sets of threshold values. A second priority ofthe one or more priorities may map to (or associate with) a second setof threshold values of the one or more sets of threshold values. Thewireless device may determine the set of threshold values, for example,based on the priority of the second sidelink transmission, and/or themapping between one or more sets of threshold values and one or morepriorities. The mapping may map/associate the set of threshold values tothe priority of the second sidelink transmission. The wireless devicemay determine the set of threshold values, for example, based on thepriority of the first sidelink transmission, and/or the mapping betweenone or more sets of threshold values and one or more priorities. Themapping may map/associate the set of threshold values to the priority ofthe first sidelink transmission. The wireless device may determine theset of threshold values, for example, based on the priority of thesecond sidelink transmission, the priority of the first sidelinktransmission, and/or the mapping between one or more sets of thresholdvalues and one or more priorities. The mapping may map/associate the setof threshold value to a combination of the priority of the firstsidelink transmission and the priority of the second sidelinktransmission. For example, the combination may be an arithmetic (e.g.,addition and/or subtraction) operation (or any other operation) of thepriority of the first sidelink transmission and the priority of thesecond sidelink transmission. A base station may send a message, to thewireless device, configuring/determining the mapping. The message maycomprise an RRC message, a MAC CE, and/or DCI. A third wireless devicemay send a message, to the wireless device, for configuring/determiningthe mapping. The message may comprise SCI. The mapping may bepre-configured. A memory associated with the wireless device may storethe pre-configured mapping. The wireless device may determine the offsetvalue based on the set of threshold values.

The wireless device may determine the offset value based on one or moreconsiderations. The wireless device may determine the offset value, forexample, based on the priority of the second sidelink transmissionand/or the priority of the first sidelink transmission, and a mappingbetween one or more sets of offset values and one or more priorities. Aset of offset values may comprise one or more offset values. Forexample, a first priority of the one or more priorities may map to (orassociate with) first set of offset values of the one or more sets ofoffset values. A second priority of the one or more priorities may mapto (or associate with) second set of offset values of the one or moresets of offset values. The wireless device may determine the offsetvalue, for example, based on the priority of the second sidelinktransmission, and the mapping between one or more sets of offset valuesand one or more priorities. The mapping may map/associate the offsetvalue to the priority of the second sidelink transmission. The wirelessdevice may determine the offset value, for example, based on thepriority of the first sidelink transmission, and the mapping between oneor more sets of offset values and one or more priorities. The mappingmay map/associate the offset value to the priority of the first sidelinktransmission. The wireless device may determine the offset value, forexample, based on the priority of the second sidelink transmission, thepriority of the first sidelink transmission, and the mapping between oneor more sets of offset values and one or more priorities. The mappingmay map/associate the offset value to a combination of the priority ofthe first sidelink transmission and the priority of the second sidelinktransmission. For example, the combination may be an arithmetic (e.g.,addition and/or subtraction) operation (or any other operation)comprising the priority of the first sidelink transmission and thepriority of the second sidelink transmission. A base station may send,to the wireless device, a for message configuring/determining themapping. The message may comprise an RRC message, a MAC CE, and/or DCI.A third wireless device may send, to the wireless device, a message forconfiguring/determining the mapping. The message may comprise SCI. Themapping may be pre-configured. A memory associated with the wirelessdevice may store the pre-configured mapping.

At step 4551d, the wireless device may exclude the second resources fromthe candidate resource set. The wireless device may exclude the secondresources, for example, based on the offset value. The wireless devicemay exclude the second resources from the candidate resource set, forexample, if the RSRP of the second sidelink transmission >(the RSRPthreshold value +the offset value). The wireless device may not excludethe second resources from the candidate resource set, for example, ifthe RSRP of the second sidelink transmission <(the RSRP threshold value+the offset value).

At step 4590, the wireless device may select third resources from thecandidate resource set. The wireless device may select third resourcesbased on the excluding the second resources from the candidate resourceset. At step 4591, the wireless device may send the first sidelinktransmission via the selected third resources.

The wireless device may perform PSFCH-based exclusion 4551 as describedwith respect to FIG. 45, for example, after the second exclusion 2250described with respect to FIG. 22. The wireless device may performPSFCH-based exclusion 4551 as described with respect to FIG. 45, forexample, within the second exclusion 2250 such as described with respectto FIG. 22 (e.g., as part of the second exclusion 2250).

FIG. 46A, FIG. 46B, and FIG. 46C show example mapping between one ormore threshold values and one or more priorities. A wireless device maytrigger a resource selection procedure for sending a first sidelinktransmission. The first sidelink transmission may have a priority Pi.The wireless device may receive a second sidelink transmission in asensing window. SCI of the second sidelink transmission may indicate apriority Pj of the second sidelink transmission. As shown in FIG. 46A,the wireless device may determine one or more threshold values based onthe priority Pi of the first sidelink transmission. FIG. 46A shows nthreshold values (e.g., Th1(Pi), Th2 (Pi), Th3(Pi),Th4(Pi), andThn(Pi)). The n threshold values may vary based on the priority Pi. Thewireless device may determine an offset value based on the one or morethreshold values. The wireless device may determine the offset value 3(e.g., O′3 in FIG. 46A), for example, if a received power Prx of PSFCHresources (e.g., signals sent via PSFCH resources) associated with thesecond sidelink transmission satisfies the condition Th2 (Pi)<Prx≤Th3(Pi). As shown in FIG. 46B, the wireless device may determineone or more threshold values based on the priority Pj of the secondsidelink transmission. FIG. 46B shows n threshold values (e.g., Th1(Pj),Thn(Pj), Th3(Pj), Th4(Pj), and Thn(Pj)). The n threshold values may varybased on the priority Pj. The wireless device may determine an offsetvalue based on the one or more threshold values. The wireless device maydetermine the offset value 3 (e.g., O′3 in FIG. 46B), for example, if areceived power Prx of PSFCH resources (e.g., signals sent via PSFCHresources) associated with the second sidelink transmission satisfiesthe condition Th2(Pj) <Prx ≤Th3(Pj). As shown in FIG. 46C, the wirelessdevice may determine one or more threshold values based on a combinationof the priority Pi of the first sidelink transmission and the priorityPj of the second sidelink transmission. For example, the combination maybe an arithmetic (e.g., addition and/or subtraction) operation (or anyother operation comprising the priority Pi and the priority Pj. FIG. 46Cshows n threshold values (e.g., Th1(Pi, Pj), Th2 (Pi, Pj), Th3 (Pi, Pj),Th4(Pi, Pj), and Th5(Pi, Pj)). The n threshold values may vary based onthe priority Pi and the priority Pj. The wireless device may determinean offset value based on the one or more threshold values. The wirelessdevice may determine the offset value 3 (e.g., O′3 in FIG. 46C), forexample, if a received power Prx of PSFCH resources (e.g., signals sentvia PSFCH resources) associated with the second sidelink transmissionsatisfies the condition Th2 (Pi, Pj) <Prx ≤Th3 (Pi, Pj).

FIG. 47A, FIG. 47B, and FIG. 47C show example mapping between one ormore offset values and one or more priorities. A wireless device maytrigger a resource selection procedure for sending a first sidelinktransmission. The first sidelink transmission may have a priority Pi.The wireless device may receive a second sidelink transmission in asensing window. SCI of the second sidelink transmission may indicate apriority Pj of the second sidelink transmission. As shown in FIG. 47A,the wireless device may determine one or more offset values based on thepriority Pi of the first sidelink transmission. FIG. 47A, shows nthreshold values (e.g., Th1, Th2, Th3, Th4, and Thn). A base station ora second wireless device may configure the n threshold values for thewireless device. The n threshold values may be preconfigured for thewireless device. The wireless device may determine the one or moreoffset values, for example, based on the one or more threshold valuesand the priority Pi of the first sidelink transmission. The wirelessdevice may determine the offset value 3 (e.g., O′3 (Pi) in FIG. 47A),for example, if a received power Prx of PSFCH resources (e.g., signalssent via PSFCH resources) associated with the second sidelinktransmission satisfies the condition Th2 <Prx ≤Th3. As shown in FIG.47B, the wireless device may determine one or more offset values basedon the priority Pi of the first sidelink transmission. FIG. 47B, shows nthreshold values (e.g., Th1, Th2, Th3, Th4, and Thn). A base station ora second wireless device may configure the n threshold values for thewireless device. The n threshold values may be preconfigured for thewireless device. The wireless device may determine the one or moreoffset values, for example, based on the one or more threshold valuesand the priority Pj of the second sidelink transmission. The wirelessdevice may determine the offset value 3 (e.g., O′3(Pj) in FIG. 47B), forexample, if a received power Prx of PSFCH resources (e.g., signals sentvia PSFCH resources) associated with the second sidelink transmissionsatisfies the condition Th2 <Prx ≤Th3. As shown in FIG. 47C, thewireless device may determine one or more offset values based on thepriority Pi of the first sidelink transmission. In an example of FIG.47C, there are n threshold values (e.g., Th1, Th2, Th3, Th4, and Thn). Abase station or a second wireless device may configure the n thresholdvalues for the wireless device. The n threshold values may bepreconfigured for the wireless device. The wireless device may determinethe one or more offset values, for example, based on the one or morethreshold values, the priority Pi of the first sidelink transmission,and the priority Pj of the second sidelink transmission. The wirelessdevice may determine the offset value 3 (e.g., O′3(Pi, Pj) in FIG. 47C),for example, if a received power Prx of PSFCH resources (e.g., signalssent via PSFCH resources) associated with the second sidelinktransmission satisfies the condition Th2 <Prx ≤Th3.

A wireless device may trigger a resource selection procedure for a firstsidelink transmission. The wireless device may determine a sensingwindow based on the triggering the resource selection procedure. Thewireless device may determine a selection window based on the triggeringthe resource selection procedure. The wireless device may initialize acandidate resource set comprising candidate resources in the selectionwindow. The wireless device may receive a second sidelink transmissionvia first resources in the sensing window. SCI of the second sidelinktransmission may indicate a priority of the second sidelink transmissionand second resources in the selection window. The wireless device maydetermine one or more PSFCH resources in the sensing window. The one ormore PSFCH resources may be associated with the first resources. Thewireless device may exclude the second resources from the candidateresource set, for example, based on the priority of the second sidelinktransmission and a measurement of the one or more PSFCH resources. Thewireless device may select third resource from the candidate resourceset based on the excluding. The wireless device may send the firstsidelink transmission via the third resources.

The measurement may comprise a received power of signals sent via theone or more PSFCH resources. The wireless device may receive one or moreRRC messages. The one or more RRC messages may comprise one or moreparameters. The one or more parameters may indicate one or morethreshold values. The wireless device may determine the one or morePSFCH resources in the sensing window, for example, based on thereceived power of signals sent via the one or more PSFCH resources beinggreater than a threshold value of the one or more threshold values. Thewireless device may determine a probability for the excluding the secondresources from the candidate resource set, for example, based on thereceived power of signals sent via the one or more PSFCH resources andthe one or more threshold values. The SCI may comprise one or moreparameters indicating resource assignment of the second resources for athird sidelink transmission. The third sidelink transmission maycomprise a same TB as included in the second sidelink transmission.

The wireless device may receive one or more RRC message. The one or moreRRC messages may comprise one or more first parameters. The one or morefirst parameters may configure one or more reservation periods of aresource pool. The SCI may further indicate a reservation period, of theone or more reservation periods, for resource reservation of the secondresources for a third sidelink transmission. The third sidelinktransmission may comprise a different TB than a TB included in thesecond sidelink transmission.

The one or more RRC messages may further comprise one or more secondparameters. The one or more second parameters may indicate a mappingbetween one or more threshold values and one or more priorities. Thewireless device may select a threshold value, from the one or morethreshold values, for example, based on the priority of the secondsidelink transmission. The wireless device may select a threshold value,from the one or more threshold values, for example, based on a priorityof the first sidelink transmission. The wireless device may select athreshold value, from the one or more threshold values, for example,based on a combination of the priority of the second sidelinktransmission and a priority of the first sidelink transmission. Thecombination may be an arithmetic operation (or any other operations)comprising the priority of the second sidelink transmission and thepriority of the first sidelink transmission. The wireless device mayexclude the second resources from the candidate resource set, forexample, based on at least one of: an RSRP of the second sidelinktransmission being greater than a RSRP threshold value, and the receivedpower of signals sent via the one or more PSFCH resources being greaterthan the threshold value.

The wireless device may determine an offset value, for example, based onthe threshold value. The wireless device may exclude the secondresources from the candidate resource set, for example, based on an RSRPof the first sidelink transmission being greater than a summation of theoffset value and an RSRP threshold value.

A wireless device may trigger a resource selection procedure for a firstsidelink transmission. The wireless device may determine a sensingwindow based on the triggering the resource selection procedure, aselection window based on the triggering the resource selectionprocedure, and one or more reservation periods for resource reservation.The wireless device may initialize a candidate resource set. Thecandidate resource set may comprise candidate resources in the selectionwindow. The wireless device may receive a second sidelink transmissionvia first resources in the sensing window. SCI of the second sidelinktransmission may indicate a priority of the second sidelinktransmission, and a reservation period, of the one or more reservationperiods, for resource reservation of second resources in the selectionwindow. The wireless device may determine one or more PSFCH resources inthe sensing window. The one or more PSFCH resources may be associatedwith the first resources. The wireless device may send the firstsidelink transmission, via the second resources, using a transmissionpower. The transmission power may be based on the priority of the secondsidelink transmission and a measurement of the one or more PSFCHresources.

A wireless device may trigger a resource selection procedure for a firstsidelink transmission. The wireless device may determine a sensingwindow based on the triggering the resource selection procedure, aselection window based on the triggering the resource selectionprocedure, and one or more reservation periods for resource reservation.The wireless device may initialize a candidate resource set. Thecandidate resource set may comprise candidate resources in the selectionwindow. The wireless device may receive a second sidelink transmission,via first resources, in the sensing window. SCI of the second sidelinktransmission may indicate a priority of the second sidelink transmissionand a reservation period, of the one or more reservation periods, forresource reservation of second resources in the selection window. Thewireless device may determine one or more PSFCH resources in the sensingwindow. The one or more PSFCH resources may be associated with the firstresources. The wireless device may exclude the second resources from thecandidate resource set, for example, based on the priority of the secondsidelink transmission and a measurement of the one or more PSFCHresources. The wireless device may select third resources from thecandidate resource set based on the excluding. The wireless device maysend the first sidelink transmission via the third resources.

A wireless device may trigger a resource selection procedure for a firstsidelink transmission. The wireless device may determine a sensingwindow based on the triggering the resource selection procedure and aselection window based on the triggering the resource selectionprocedure. The wireless device may initialize a candidate resource set.The candidate resource set may comprise candidate resources in theselection window. The wireless device may receive a second sidelinktransmission, via first resources, in the sensing window. SCI of thesecond sidelink transmission may indicate a priority of the secondsidelink transmission and second resources in the selection window. Thewireless device may determine one or more PSFCH resources in the sensingwindow. The one or more PSFCH resources may be associated with the firstresources. The wireless device may determine an offset value, forexample, based on a measurement of the one or more PSFCH resources, aset of threshold values, and the priority of the second sidelinktransmission. The wireless device may exclude the second resources fromthe candidate resource set, for example, based on an RSRP of the secondsidelink transmission being greater than a summation of an RSRPthreshold value and the offset value. The wireless device may selectthird resource from the candidate resource set based on the excluding.The wireless device may send the first sidelink transmission via thethird resources.

A first wireless device may perform a method comprising multipleoperations. The first wireless device may receive, via a first resourceoccurring in a sensing time period, control information indicatingassignment of a second resource, occurring in a selection time period,for wireless communication by a second wireless device. The firstwireless device may determine a received power of one or more feedbackchannel resources associated with the first resource. The first wirelessdevice may determine, based on the received power of the one or morefeedback channel resources satisfying a threshold, a third resourceoccurring in the selection time period. The first wireless device maytransmit, via the third resource, a message to a third wireless device.The first wireless device may also perform one or more additionaloperations. The determining the third resource may comprise selectingthe third resource from among a candidate resource set such that one ormore reserved resources are excluded from selection as the thirdresource. The excluding the one or more reserved resources fromselection as the third resource may be based on a probabilitycorresponding to the threshold. The first wireless device may receive atleast one configuration parameter indicating at least one of: thesensing time period; or the selection time period. The determining thereceived power of the one or more feedback channel resources associatedwith the first resource may comprise measuring a received power of oneor more physical sidelink feedback channel (PSFCH) resources associatedwith the first resource. The control information may indicate one ormore resource reservations of a candidate resource set. Determining thethird resource may comprise excluding each resource, of the one or moreresource reservations of the candidate resource set, that is associatedwith a feedback channel corresponding to a received power that isgreater than a threshold. The determining the third resource may befurther based on at least one of: a received signal received power(RSRP), associated with the receiving the control information, beinggreater than a threshold; or the received power of the one or morefeedback channel resources being greater than the threshold. The firstwireless device may receive an indication of a priority associated withthe second resource. The determining the third resource may be furtherbased on at least one of: the priority associated with the secondresource; or a priority associated with the message. The determining thethird resource may be further based on a summation of received signalreceived power (RSRP), associated with the receiving the controlinformation, and an offset value being greater than a threshold. Thecontrol information may be for a second message from the second wirelessdevice. The second message may be the same as the message. The thresholdvalue may be based on a cast type of the wireless communication by thesecond wireless device. The first wireless device may comprise one ormore processors; and memory storing instructions that, when executed bythe one or more processors, cause the first wireless device to performthe described method, additional operations and/or include theadditional elements. A system may comprise the firstwireless deviceconfigured to perform the described method, additional operations and/orinclude the additional elements; and a base station configured to sendthe control information. A computer-readable medium may storeinstructions that, when executed, cause performance of the describedmethod, additional operations and/or include the additional elements.

A first wireless device may perform a method comprising multipleoperations. The first wireless device may receive at least oneconfiguration parameter for selection of one or more resources tocommunicate with a second wireless device. The at least oneconfiguration parameter may indicate a sensing time period and aselection time period. The first wireless device may receive, via afirst resource occurring in the sensing time period, control informationindicating assignment of a second resource, occurring in the selectiontime period, for wireless communication by a third wireless device. Thefirst wireless device may determine, based on a received power of one ormore feedback channel resources associated with the second resource, athird resource occurring in the selection time period. The firstwireless device may transmit, via the third resource, a message to thesecond wireless device The first wireless device may also perform one ormore additional operations. The first wireless device may determine thereceived power of the one or more feedback channel resources associatedwith the second resource. The determining the received power of the oneor more feedback channel resources associated with the first resourcemay comprise measuring a received power of one or more physical sidelinkfeedback channel (PSFCH) resources associated with the first resource.The determining the third resource may comprise selecting the thirdresource from among a candidate resource set such that one or morereserved resources of the candidate resource set are excluded fromselection as the third resource. The control information may indicateone or more resource reservations of a candidate resource set.Determining the third resource may comprise excluding each resource, ofthe one or more resource reservations of the candidate resource set,that is associated with a feedback channel corresponding to a receivedpower that is greater than a threshold. The determining the thirdresource may be further based on at least one of: a received signalreceived power (RSRP), associated with the receiving the controlinformation, being greater than a threshold; or the received power ofthe one or more feedback channel resources being greater than thethreshold. The first wireless device may receive an indication of apriority associated with the second resource. The determining the thirdresource may be further based on at least one of: the priorityassociated with the second resource; or a priority associated with themessage. The first wireless device may comprise one or more processors;and memory storing instructions that, when executed by the one or moreprocessors, cause the first wireless device to perform the describedmethod, additional operations and/or include the additional elements. Asystem may comprise the first wireless device configured to perform thedescribed method, additional operations and/or include the additionalelements; and a base station configured to send the at least oneconfiguration parameter. A computer-readable medium may storeinstructions that, when executed, cause performance of the describedmethod, additional operations and/or include the additional elements.

A first wireless device may perform a method comprising multipleoperations. The first wireless device may receive at least oneconfiguration parameter for selection of one or more resources tocommunicate with a second wireless device The at least one configurationparameter may indicate a sensing time period for sensing transmissionfrom a third wireless device. The first wireless device may determine afirst resource from a candidate resource set. The first resource may bedetermined based on: control information received via a second resourceoccurring in the sensing time period, wherein the control informationindicates one or more resource reservations of the candidate resourceset; and a measurement of one or more feedback channel resourcesassociated with the second resource. The first wireless device maytransmit, via the first resource, a message to the second wirelessdevice. The first wireless device may also perform one or moreadditional operations. The first wireless device may determine themeasurement of the one or more feedback channel resources associatedwith the second resource by measuring a received power of one or morephysical sidelink feedback channel (PSFCH) resources associated with thethe second resource. The determining the first resource may compriseselecting the first resource from the candidate resource set such thatone or more reserved resources of the candidate resource set areexcluded from selection as the first resource. The first wireless devicemay receive the control information. The control information mayindicate one or more resource reservations of the candidate resourceset. The determining the first resource may comprise excluding eachresource, of the candidate resource set, that is associated with afeedback channel corresponding to a received power that is greater thana threshold. The determining the first resource may be further based onat least one of: a received signal received power (RSRP), associatedwith the receiving the control information, being greater than athreshold; or the received power of the one or more feedback channelresources being greater than the threshold. The first wireless devicemay receive an indication of a priority associated with the secondresource. The determining the first resource may be further based on atleast one of: the priority associated with the second resource; or apriority associated with the message. The first wireless device maycomprise one or more processors; and memory storing instructions that,when executed by the one or more processors, cause the first wirelessdevice to perform the described method, additional operations and/orinclude the additional elements. A system may comprise the firstwireless device configured to perform the described method, additionaloperations and/or include the additional elements; and a base stationconfigured to send the at least one configuration parameter. Acomputer-readable medium may store instructions that, when executed,cause performance of the described method, additional operations and/orinclude the additional elements.

A wireless device may perform a method comprising multiple operations.The wireless device may trigger a resource selection procedure for asidelink transmission. The wireless device may determine: a sensingwindow based on the triggering the resource selection procedure; aselection window based on the triggering the resource selectionprocedure; and one or more reservation periods for resource reservation.The wireless device may determine a received power of one or morephysical sidelink feedback channel (PSFCH) resources in the sensingwindow. The wireless device may determine first resources in the sensingwindow. The first resources may be associated with the one or more PSFCHresources. The wireless device may determine second resources in theselection window based on: the first resources; and the one or morereservation periods. The wireless device may transmit the sidelinktransmission via the second resources with a transmission power based onthe received power of the one or more PSFCH resources. The wirelessdevice may also perform one or more additional operations. The wirelessdevice may comprise one or more processors; and memory storinginstructions that, when executed by the one or more processors, causethe wireless device to perform the described method, additionaloperations and/or include the additional elements. A system may comprisethe wireless device configured to perform the described method,additional operations and/or include the additional elements; and asecond wireless device configured to receive the sidelink transmission.A computer-readable medium may store instructions that, when executed,cause performance of the described method, additional operations and/orinclude the additional elements.

A wireless device may perform a method comprising multiple operations.The wireless device may trigger a resource selection procedure for asidelink transmission. The wireless device may determine: a sensingwindow based on the triggering the resource selection procedure; and aselection window based on the triggering the resource selectionprocedure. The wireless device may receive sidelink control information(SCI) via first resources in the sensing window. The SCI may indicateresource assignment of second resources in the selection window. Thewireless device may determine a received power of one or more physicalsidelink feedback channel (PSFCH) resources in the sensing window,wherein the one or more PSFCH resources may be associated with the firstresources. The wireless device may transmit the sidelink transmissionvia the second resources with a transmission power based on the receivedpower of the one or more PSFCH resources. The wireless device may alsoperform one or more additional operations. The wireless device maycomprise one or more processors; and memory storing instructions that,when executed by the one or more processors, cause the wireless deviceto perform the described method, additional operations and/or includethe additional elements. A system may comprise the wireless deviceconfigured to perform the described method, additional operations and/orinclude the additional elements; and a second wireless device configuredto receive the sidelink transmission. A computer-readable medium maystore instructions that, when executed, cause performance of thedescribed method, additional operations and/or include the additionalelements.

A wireless device may perform a method comprising multiple operations.The wireless device may trigger a resource selection procedure for asidelink transmission. The wireless device may determine: a sensingwindow based on the triggering the resource selection procedure; aselection window based on the triggering the resource selectionprocedure; and one or more reservation periods for resource reservation.The wireless device may initialize a candidate resource set comprisingcandidate resources in the selection window. The wireless device maydetermine one or more physical sidelink feedback channel (PSFCH)resources in the sensing window based on a measurement of the one ormore PSFCH resources. The wireless device may exclude second resourcesfrom the candidate resource set based on: first resources in the sensingwindow, wherein the first resources are associated with the one or morePSFCH resources; and the one or more reservation periods. The wirelessdevice may select third resource from the candidate resource set basedon the excluding. The wireless device may transmit the sidelinktransmission via the third resources. The wireless device may alsoperform one or more additional operations. The wireless device maycomprise one or more processors; and memory storing instructions that,when executed by the one or more processors, cause the wireless deviceto perform the described method, additional operations and/or includethe additional elements. A system may comprise the wireless deviceconfigured to perform the described method, additional operations and/orinclude the additional elements; and a second wireless device configuredto receive the sidelink transmission. A computer-readable medium maystore instructions that, when executed, cause performance of thedescribed method, additional operations and/or include the additionalelements.

A wireless device may perform a method comprising multiple operations.The wireless device may trigger a resource selection procedurecomprising: a sensing window for sensing sidelink transmissions; and aselection window for selecting resources for a first sidelinktransmission. The wireless device may initialize a candidate resourceset comprising candidate resources in the selection window. The wirelessdevice may exclude a first resource from the candidate resource setbased on: SCI, received via a second resource in the sensing window,indicating a resource reservation of the first resource; and ameasurement of one or more physical sidelink feedback channel (PSFCH)resources associated with the second resource being greater than athreshold. The wireless device may transmit, via one or more resourcesof the candidate resource set other than the first resource, the firstsidelink transmission. The wireless device may also perform one or moreadditional operations. The wireless device may comprise one or moreprocessors; and memory storing instructions that, when executed by theone or more processors, cause the wireless device to perform thedescribed method, additional operations and/or include the additionalelements. A system may comprise the wireless device configured toperform the described method, additional operations and/or include theadditional elements; and a second wireless device configured to receivethe first sidelink transmission. A computer-readable medium may storeinstructions that, when executed, cause performance of the describedmethod, additional operations and/or include the additional elements.

A wireless device may perform a method comprising multiple operations.The wireless device may receive configuration parameters for a resourceselection procedure. The configuration parameters may indicate: asensing window for sensing sidelink transmissions; and a selectionwindow for selecting resources for a first sidelink transmission. Thewireless device may determine a candidate resource set comprisingcandidate resources in the selection window. The wireless device maytransmit, via one or more resources of the candidate resource set, thefirst sidelink transmission (e.g., wherein the one or more resourcesdoes not comprise a first resource from the candidate resource set),based on: SCI, received via a second resource in the sensing window,indicating a resource reservation of the first resource; and ameasurement of one or more physical sidelink feedback channel (PSFCH)resources associated with the second resource being greater than athreshold. The wireless device may also perform one or more additionaloperations. The wireless device may comprise one or more processors; andmemory storing instructions that, when executed by the one or moreprocessors, cause the wireless device to perform the described method,additional operations and/or include the additional elements. A systemmay comprise the wireless device configured to perform the describedmethod, additional operations and/or include the additional elements;and a second wireless device configured to receive the first sidelinktransmission. A computer-readable medium may store instructions that,when executed, cause performance of the described method, additionaloperations and/or include the additional elements.

A wireless device may perform a method comprising multiple operations.The wireless device may trigger, for a first sidelink transmission, aresource selection procedure comprising: a sensing window; and aselection window. The wireless device may initialize a candidateresource set comprising candidate resources in the selection window. Thewireless device may exclude, a first resource from the candidateresource set, based on: SCI, received via a second resource in thesensing window, indicating a resource reservation of the first resource;and a measurement of one or more physical sidelink feedback channel(PSFCH) resources associated with the second resource. The wirelessdevice may transmit, based on the candidate resource set excluding thefirst resource, the first sidelink transmission. The wireless device mayalso perform one or more additional operations. The wireless device maycomprise one or more processors; and memory storing instructions that,when executed by the one or more processors, cause the wireless deviceto perform the described method, additional operations and/or includethe additional elements. A system may comprise the wireless deviceconfigured to perform the described method, additional operations and/orinclude the additional elements; and a second wireless device configuredto receive the first sidelink transmission. A computer-readable mediummay store instructions that, when executed, cause performance of thedescribed method, additional operations and/or include the additionalelements.

A wireless device may perform a method comprising multiple operations.The wireless device may receive at least one configuration parameterindicating a set of received power ranges associated with a firstpriority and a second priority. The first priority may be associatedwith communication between the first wireless device and a secondwireless device. The wireless device may receive, via a first resource,control information indicating: the second priority; and/or areservation of a second resource. The wireless device may determine areceived power range, from the set of received power ranges, comprisinga value of a received power measurement of one or more feedback channelresources associated with the first resource. The wireless device maydetermine, based on the received power range and at least one of thefirst priority or the second priority, a third resource forcommunication between the first wireless device and the second wirelessdevice. The wireless device may transmit, via the third resource, amessage to the second wireless device. The wireless device may determinea candidate resource set comprising resources occurring in a selectiontime period, wherein the determining the third resource comprisesselecting the third resource from the candidate resource set. The one ormore feedback channel resources may comprise one or more physicalsidelink feedback channel (PSFCH) resources. The wireless device maydetermine the third resource by excluding, from selection as the thirdresource, each resource, of the one or more feedback channel resources,corresponding to a received power range satisfying a threshold. Thewireless device may determine, based on the received power range, atransmission power for transmission of the message. The wireless devicemay transmit the message using the transmission power. The at least oneconfiguration parameter further may indicate: a sensing time period forthe receiving the control information; and/or a selection time periodduring which the second resource occurs and during which the thirdresource occurs. The second priority may be higher than the firstpriority. The wireless device may determine the third resource forcommunication with the second wireless device by excluding, from among acandidate resource set comprising the third resource, one or moreresources associated with the second priority. The wireless device maycomprise one or more processors; and memory storing instructions that,when executed by the one or more processors, cause the wireless deviceto perform the described method, additional operations and/or includethe additional elements. A system may comprise the wireless deviceconfigured to perform the described method, additional operations and/orinclude the additional elements; and at least one of: a second wirelessdevice configured to receive the message and/or a sidelink transmission,and/or a base station configured to send configuration parameters. Acomputer-readable medium may store instructions that, when executed,cause performance of the described method, additional operations and/orinclude the additional elements.

A wireless device may perform a method comprising multiple operations.The wireless device may receive at least one configuration parameter forselection of one or more resources to communicate with a second wirelessdevice. The at least one configuration parameter may indicate a sensingtime period and a selection time period. The wireless device mayreceive, via a first resource occurring in the sensing time period,control information indicating: a reservation of a second resource;and/or a priority associated with the second resource. The wirelessdevice may determine a received power range, from a set of receivedpower ranges, comprising a value of a received power measurement of oneor more feedback channel resources associated with the first resource.The wireless device may determine, based on the received power range andthe priority, a third resource occurring in the selection time period.The wireless device may transmit, via the third resource, a message tothe second wireless device. The wireless device may determine acandidate resource set comprising resources occurring in the selectiontime period. The wireless device may determine the third resource byselecting the third resource from the candidate resource set. Thewireless device may determine a received power of one or more feedbackchannel resources associated with the second resource. The wirelessdevice may determine the third resource based on the received power ofthe one or more feedback channel resources associated with the secondresource. The one or more feedback channel resources may comprise one ormore physical sidelink feedback channel (PSFCH) resources. The wirelessdevice may determine the third resource by excluding, from selection asthe third resource. Each resource, of the one or more feedback channelresources, may correspond to a received power range satisfying athreshold. The wireless device may determine, based on the receivedpower range, a transmission power for transmission of the message. Thewireless device may transmit the message using the transmission power.The priority associated with the second resource may comprise a firstpriority that is higher than a second priority associated withcommunication between the first wireless device and the second wirelessdevice. The wireless device may determine the third resource byexcluding, from among a candidate resource set comprising the thirdresource, one or more resources associated with the first priority. Thewireless device may comprise one or more processors; and memory storinginstructions that, when executed by the one or more processors, causethe wireless device to perform the described method, additionaloperations and/or include the additional elements. A system may comprisethe wireless device configured to perform the described method,additional operations and/or include the additional elements; and atleast one of: a second wireless device configured to receive the messageand/or a sidelink transmission, and/or a base station configured to sendconfiguration parameters. A computer-readable medium may storeinstructions that, when executed, cause performance of the describedmethod, additional operations and/or include the additional elements.

A wireless device may perform a method comprising multiple operations.The wireless device may receive at least one configuration parameter forselection of one or more resources to communicate with a second wirelessdevice. The wireless device may receive, via a first resource, controlinformation indicating: a reservation of a second resource; and/or afirst priority associated with the second resource. The wireless devicemay determine a received power range, from a set of received powerranges, comprising a value of a received power measurement of one ormore feedback channel resources associated with the first resource. Thewireless device may determine, based on received power range and basedon at least one of the first priority or a second priority associatedwith a communication between the first wireless device and the secondwireless device, a third resource. The wireless device may transmit, viathe third resource, a message to the second wireless device. Thewireless device may determine a candidate resource set comprisingresources occurring in a selection time period, wherein the determiningthe third resource comprises selecting the third resource from thecandidate resource set. The wireless device may determine a receivedpower of one or more feedback channel resources associated with thesecond resource. The wireless device may determine the third resourcebased on the received power of the one or more feedback channelresources associated with the second resource. The one or more feedbackchannel resources may comprise one or more physical sidelink feedbackchannel (PSFCH) resources. The wireless device may determine, based onthe received power range, a transmission power for transmission of themessage. The wireless device may transmit the message using thetransmission power. The at least one configuration parameter mayindicate the first priority. The first priority may be higher than thesecond priority. The wireless device may determine the third resource byexcluding, from among a candidate resource set comprising the thirdresource, one or more resources associated with the first priority. Thewireless device may comprise one or more processors; and memory storinginstructions that, when executed by the one or more processors, causethe wireless device to perform the described method, additionaloperations and/or include the additional elements. A system may comprisethe wireless device configured to perform the described method,additional operations and/or include the additional elements; and atleast one of: a second wireless device configured to receive the messageand/or a sidelink transmission, and/or a base station configured to sendconfiguration parameters. A computer-readable medium may storeinstructions that, when executed, cause performance of the describedmethod, additional operations and/or include the additional elements.

A wireless device may perform a method comprising multiple operations.The wireless device may receive, for a resource selection procedure of afirst sidelink transmission having a first priority, configurationparameters indicating a set of received power ranges associated with thefirst priority and a second priority. The wireless device may determinea candidate resource set comprising candidate resources in a selectionwindow. The wireless device may receive, via a second resource, asidelink control information (SCI) of a second sidelink transmissionindicating: the second priority; and/or a resource reservation of afirst resource. The wireless device may determine a received powerrange, from the set of received power ranges, including a value of areceived power measurement of one or more physical sidelink feedbackchannel (PSFCH) resources associated with the second resource. Thewireless device may exclude, based on the received power range, thefirst resource from the candidate resource set. The wireless device maytransmit, via one or more resources of the candidate resource set otherthan the first resource, the first sidelink transmission. Theconfiguration parameters may comprise: a sensing window; and/or theselection window. The wireless device may receive the SCI of the secondsidelink transmission by receiving the SCI of the second sidelinktransmissions in the sensing window. The wireless device may receive theconfiguration parameters by receiving one or more radio resource control(RRC) messages. The one or more RRC messages may comprise theconfiguration parameters. The one or more RRC messages may comprise oneor more first parameters indicating a set of threshold values. The setof threshold values may comprise a first threshold value and a secondthreshold value. The received power range may be bounded by the firstthreshold value and the second threshold value. The wireless device maydetermine a probability for the excluding of the first resource from thecandidate resource set based on the probability being corresponding tothe received power range. The wireless device may exclude the firstresource by excluding, based on the probability, the first resource fromthe candidate resource set. The wireless device may determine an offsetvalue for the excluding of the first resource from the candidateresource set based on the offset value being corresponding to thereceived power range. The wireless device may exclude the first resourceby excluding, based on a reference signal received power (RSRP) of thefirst sidelink transmission being higher than summation of the offsetvalue and a RSRP threshold value, the first resource from the candidateresource set. The first sidelink transmission may comprise a sametransport block (TB) as the second sidelink transmission. The firstsidelink transmission may comprise a different TB than the secondsidelink transmission. The wireless device may comprise one or moreprocessors; and memory storing instructions that, when executed by theone or more processors, cause the wireless device to perform thedescribed method, additional operations and/or include the additionalelements. A system may comprise the wireless device configured toperform the described method, additional operations and/or include theadditional elements; and at least one of: a second wireless deviceconfigured to receive the message and/or a sidelink transmission, and/ora base station configured to send configuration parameters. Acomputer-readable medium may store instructions that, when executed,cause performance of the described method, additional operations and/orinclude the additional elements.

A wireless device may perform a method comprising multiple operations.The wireless device mayreceive, for a resource selection procedure of afirst sidelink transmission having a first priority, configurationparameters indicating a set of received power ranges associated with atleast one of: the first priority; and/or a second priority. The wirelessdevice may determine a candidate resource set comprising candidateresources in a selection window. The wireless device may receive, via asecond resource, a sidelink control information (SCI) of a secondsidelink transmission indicating: the second priority; and/or a resourcereservation of a first resource. The wireless device may determine areceived power range, from the set of received power ranges, including avalue of a received power measurement of one or more physical sidelinkfeedback channel (PSFCH) resources associated with the second resource.The wireless device may exclude the first resource from the candidateresource set based on the received power range. The wireless device maytransmit, via one or more resources of the candidate resource set otherthan the first resource, the first sidelink transmission. The wirelessdevice may comprise one or more processors; and memory storinginstructions that, when executed by the one or more processors, causethe wireless device to perform the described method, additionaloperations and/or include the additional elements. A system may comprisethe wireless device configured to perform the described method,additional operations and/or include the additional elements; and atleast one of: a second wireless device configured to receive the messageand/or a sidelink transmission, and/or a base station configured to sendconfiguration parameters. A computer-readable medium may storeinstructions that, when executed, cause performance of the describedmethod, additional operations and/or include the additional elements.

A wireless device may perform a method comprising multiple operations.The wireless device may receive, for a resource selection procedure of afirst sidelink transmission having a first priority, configurationparameters indicating a set of received power ranges associated with atleast one of: the first priority; and/or a second priority. The wirelessdevice may determine a candidate resource set comprising candidateresources in a selection window. The wireless device may receive, via asecond resource, a sidelink control information (SCI) of a secondsidelink transmission indicating: the second priority; and/or a resourcereservation of a first resource. The wireless device may determine areceived power range, from the set of received power ranges, comprisinga value of a received power measurement of one or more physical sidelinkfeedback channel (PSFCH) resources associated with the second resource.The wireless device may determine a transmission power based on thereceived power range. The wireless device may transmit, via the firstresource and with the transmission power, the first sidelinktransmission. The wireless device may comprise one or more processors;and memory storing instructions that, when executed by the one or moreprocessors, cause the wireless device to perform the described method,additional operations and/or include the additional elements. A systemmay comprise the wireless device configured to perform the describedmethod, additional operations and/or include the additional elements;and at least one of: a second wireless device configured to receive themessage and/or a sidelink transmission, and/or a base station configuredto send configuration parameters. A computer-readable medium may storeinstructions that, when executed, cause performance of the describedmethod, additional operations and/or include the additional elements.

A wireless device may perform a method comprising multiple operations.The wireless device may receive configuration parameters, for a resourceselection procedure, comprising: a sensing window for sensing sidelinktransmissions; a selection window for selecting resources for a firstsidelink transmission having a first priority; and/or a set of thresholdvalues comprising a first threshold value and a second threshold value.The set of threshold values may be associated with at least one of: thefirst priority; and/or a second priority. The wireless device maydetermine a candidate resource set comprising candidate resources in theselection window. The wireless device may receive, via a second resourcein the sensing window, a sidelink control information (SCI) of a secondsidelink transmission indicating: the second priority; and/or a resourcereservation of a first resource. The wireless device may exclude thefirst resource from the candidate resource set based on: a measurementof one or more physical sidelink feedback channel (PSFCH) resources,associated with the second resource, being higher than the firstthreshold value; and/or the measurement of the one or more PSFCHresources being lower than the second threshold value. The wirelessdevice may transmit, via one or more resources of the candidate resourceset other than the first resource, the first sidelink transmission. Thewireless device may comprise one or more processors; and memory storinginstructions that, when executed by the one or more processors, causethe wireless device to perform the described method, additionaloperations and/or include the additional elements. A system may comprisethe wireless device configured to perform the described method,additional operations and/or include the additional elements; and atleast one of: a second wireless device configured to receive the messageand/or a sidelink transmission, and/or a base station configured to sendconfiguration parameters. A computer-readable medium may storeinstructions that, when executed, cause performance of the describedmethod, additional operations and/or include the additional elements.

A wireless device may perform a method comprising multiple operations.The wireless device may receive, for a resource selection procedure,configuration parameters indicating: a sensing window for sensingsidelink transmissions; a selection window for selecting resources for afirst sidelink transmission having a first priority; and/or a set ofreceived power ranges associated with at least one of: the firstpriority; and/or a second priority. The wireless device may determine acandidate resource set comprising candidate resources in the selectionwindow. The wireless device may receive, via a second resource in thesensing window, a sidelink control information (SCI) of a secondsidelink transmission indicating: the second priority; and/or a resourcereservation of a first resource. The wireless device may determine areceived power range, from the set of received power ranges, including avalue of a received power measurement of one or more physical sidelinkfeedback channel (PSFCH) resources associated with the second resource.The wireless device may exclude the first resource from the candidateresource set based on the received power range. The wireless device maytransmit, via one or more resources of the candidate resource set otherthan the first resource, the first sidelink transmission. The wirelessdevice may comprise one or more processors; and memory storinginstructions that, when executed by the one or more processors, causethe wireless device to perform the described method, additionaloperations and/or include the additional elements. A system may comprisethe wireless device configured to perform the described method,additional operations and/or include the additional elements; and atleast one of: a second wireless device configured to receive the messageand/or a sidelink transmission, and/or a base station configured to sendconfiguration parameters. A computer-readable medium may storeinstructions that, when executed, cause performance of the describedmethod, additional operations and/or include the additional elements.

A wireless device may perform a method comprising multiple operations.The wireless device may receive, for a resource selection procedure of afirst sidelink transmission having a first priority, configurationparameters indicating: a set of offset values associated with at leastone of: the first priority value; and/or a second priority value; and/ora set of received power ranges associated to the set of offset values.The wireless device may determine a candidate resource set comprisingcandidate resources in a selection window. The wireless device mayreceive, via a second resource, a sidelink control information (SCI) ofa second sidelink transmission indicating: the second priority; and/or aresource reservation of a first resource. The wireless device maydetermine a received power range, from the set of received power ranges,including a value of a received power measurement of one or morephysical sidelink feedback channel (PSFCH) resources associated with thesecond resource. The wireless device may exclude, based on an offsetvalue associated with the received power range, the first resource fromthe candidate resource set. The wireless device may transmit, via one ormore resources of the candidate resource set other than the firstresource, the first sidelink transmission. The wireless device maycomprise one or more processors; and memory storing instructions that,when executed by the one or more processors, cause the wireless deviceto perform the described method, additional operations and/or includethe additional elements. A system may comprise the wireless deviceconfigured to perform the described method, additional operations and/orinclude the additional elements; and at least one of: a second wirelessdevice configured to receive the message and/or a sidelink transmission,and/or a base station configured to send configuration parameters. Acomputer-readable medium may store instructions that, when executed,cause performance of the described method, additional operations and/orinclude the additional elements.

One or more of the operations described herein may be conditional. Forexample, one or more operations may be performed if certain criteria aremet, such as in a wireless device, a base station, a radio environment,a network, a combination of the above, and/or the like. Example criteriamay be based on one or more conditions such as wireless device and/ornetwork node configurations, traffic load, initial system set up, packetsizes, traffic characteristics, a combination of the above, and/or thelike. If the one or more criteria are met, various examples may be used.It may be possible to implement any portion of the examples describedherein in any order and based on any condition.

A base station may communicate with one or more of wireless devices.Wireless devices and/or base stations may support multiple technologies,and/or multiple releases of the same technology. Wireless devices mayhave some specific capability(ies) depending on wireless device categoryand/or capability(ies). A base station may comprise multiple sectors,cells, and/or portions of transmission entities. A base stationcommunicating with a plurality of wireless devices may refer to a basestation communicating with a subset of the total wireless devices in acoverage area. Wireless devices referred to herein may correspond to aplurality of wireless devices compatible with a given LTE, 5G, or other3GPP or non-3GPP release with a given capability and in a given sectorof a base station. A plurality of wireless devices may refer to aselected plurality of wireless devices, a subset of total wirelessdevices in a coverage area, and/or any group of wireless devices. Suchdevices may operate, function, and/or perform based on or according todrawings and/or descriptions herein, and/or the like. There may be aplurality of base stations and/or a plurality of wireless devices in acoverage area that may not comply with the disclosed methods, forexample, because those wireless devices and/or base stations may performbased on older releases of LTE, 5G, or other 3GPP or non-3GPPtechnology.

One or more parameters, fields, and/or information elements (IEs), maycomprise one or more information objects, values, and/or any otherinformation. An information object may comprise one or more otherobjects. At least some (or all) parameters, fields, IEs, and/or the likemay be used and can be interchangeable depending on the context. If ameaning or definition is given, such meaning or definition controls.

One or more elements in examples described herein may be implemented asmodules. A module may be an element that performs a defined functionand/or that has a defined interface to other elements. The modules maybe implemented in hardware, software in combination with hardware,firmware, wetware (e.g., hardware with a biological element) or acombination thereof, all of which may be behaviorally equivalent. Forexample, modules may be implemented as a software routine written in acomputer language configured to be executed by a hardware machine (suchas C, C++, Fortran, Java, Basic, Matlab or the like) or amodeling/simulation program such as Simulink, Stateflow, GNU Octave, orLabVIEWMathScript. Additionally, it may be possible to implement modulesusing physical hardware that incorporates discrete or programmableanalog, digital and/or quantum hardware. Examples of programmablehardware may comprise: computers, microcontrollers, microprocessors,application-specific integrated circuits (ASICs); field programmablegate arrays (FPGAs); and/or complex programmable logic devices (CPLDs).Computers, microcontrollers and/or microprocessors may be programmedusing languages such as assembly, C, C++ or the like. FPGAs, ASICs andCPLDs are often programmed using hardware description languages (HDL),such as VHSIC hardware description language (VHDL) or Verilog, which mayconfigure connections between internal hardware modules with lesserfunctionality on a programmable device. The technologies as describedherein may be used in combination to achieve the result of a functionalmodule.

One or more features described herein may be implemented in acomputer-usable data and/or computer-executable instructions, such as inone or more program modules, executed by one or more computers or otherdevices. Generally, program modules include routines, programs, objects,components, data structures, etc. that perform particular tasks orimplement particular abstract data types when executed by a processor ina computer or other data processing device. The computer executableinstructions may be stored on one or more computer readable media suchas a hard disk, optical disk, removable storage media, solid statememory, RAM, etc. The functionality of the program modules may becombined or distributed as desired. The functionality may be implementedin whole or in part in firmware or hardware equivalents such asintegrated circuits, field programmable gate arrays (FPGA), and thelike. Particular data structures may be used to more effectivelyimplement one or more features described herein, and such datastructures are contemplated within the scope of computer executableinstructions and computer-usable data described herein.

A non-transitory tangible computer readable media may compriseinstructions executable by one or more processors configured to causeoperations of multi-carrier communications described herein. An articleof manufacture may comprise a non-transitory tangible computer readablemachine-accessible medium having instructions encoded thereon forenabling programmable hardware to cause a device (e.g., a wirelessdevice, wireless communicator, a wireless device, a base station, andthe like) to allow operation of multi-carrier communications describedherein. The device, or one or more devices such as in a system, mayinclude one or more processors, memory, interfaces, and/or the like.Other examples may comprise communication networks comprising devicessuch as base stations, wireless devices or user equipment (wirelessdevice), servers, switches, antennas, and/or the like. A network maycomprise any wireless technology, including but not limited to,cellular, wireless, WiFi, 4G, 5G, any generation of 3GPP or othercellular standard or recommendation, any non-3GPP network, wirelesslocal area networks, wireless personal area networks, wireless ad hocnetworks, wireless metropolitan area networks, wireless wide areanetworks, global area networks, satellite networks, space networks, andany other network using wireless communications. Any device (e.g., awireless device, a base station, or any other device) or combination ofdevices may be used to perform any combination of one or more of stepsdescribed herein, including, for example, any complementary step orsteps of one or more of the above steps.

Although examples are described herein, features and/or steps of thoseexamples may be combined, divided, omitted, rearranged, revised, and/oraugmented in any desired manner Various alterations, modifications, andimprovements will readily occur to those skilled in the art. Suchalterations, modifications, and improvements are intended to be part ofthis description, though not expressly stated herein, and are intendedto be within the spirit and scope of the descriptions herein.Accordingly, the foregoing description is by way of example only, and isnot limiting.

What is claimed is:
 1. A method comprising: receiving, by a firstwireless device via a first resource occurring in a sensing time period,control information indicating assignment of a second resource,occurring in a selection time period, for wireless communication by asecond wireless device; determining a received power of one or morefeedback channel resources associated with the first resource; based onthe received power of the one or more feedback channel resourcessatisfying a threshold, determining a third resource occurring in theselection time period; and transmitting, by the first wireless devicevia the third resource, a message to a third wireless device.
 2. Themethod of claim 1, wherein the determining the third resource comprises:selecting the third resource from among a candidate resource set suchthat one or more reserved resources are excluded from selection as thethird resource.
 3. The method of claim 1, further comprising receivingat least one configuration parameter indicating at least one of: thesensing time period; or the selection time period.
 4. The method ofclaim 1, wherein the determining the received power of the one or morefeedback channel resources associated with the first resource comprises:measuring a received power of one or more physical sidelink feedbackchannel (PSFCH) resources associated with the first resource.
 5. Themethod of claim 1, wherein the control information indicates one or moreresource reservations of a candidate resource set, and whereindetermining the third resource comprises excluding each resource, of theone or more resource reservations of the candidate resource set, that isassociated with a feedback channel corresponding to a received powerthat is greater than a threshold.
 6. The method of claim 1, wherein thedetermining the third resource is further based on at least one of: areceived signal received power (RSRP), associated with the receiving thecontrol information, being greater than a threshold; or the receivedpower of the one or more feedback channel resources being greater thanthe threshold.
 7. The method of claim 1, further comprising: receivingan indication of a priority associated with the second resource, whereinthe determining the third resource is further based on at least one of:the priority associated with the second resource; or a priorityassociated with the message.
 8. A method comprising: receiving, by afirst wireless device, at least one configuration parameter forselection of one or more resources to communicate with a second wirelessdevice, wherein the at least one configuration parameter indicates asensing time period and a selection time period; receiving, via a firstresource occurring in the sensing time period, control informationindicating assignment of a second resource, occurring in the selectiontime period, for wireless communication by a third wireless device;determining, based on a received power of one or more feedback channelresources associated with the second resource, a third resourceoccurring in the selection time period; and transmitting, by the firstwireless device via the third resource, a message to the second wirelessdevice.
 9. The method of claim 8, further comprising: determining thereceived power of the one or more feedback channel resources associatedwith the second resource.
 10. The method of claim 9, wherein thedetermining the received power of the one or more feedback channelresources associated with the first resource comprises: measuring areceived power of one or more physical sidelink feedback channel (PSFCH)resources associated with the first resource.
 11. The method of claim 8,wherein the determining the third resource comprises: selecting thethird resource from among a candidate resource set such that one or morereserved resources of the candidate resource set are excluded fromselection as the third resource.
 12. The method of claim 8, wherein thecontrol information indicates one or more resource reservations of acandidate resource set, and wherein determining the third resourcecomprises excluding each resource, of the one or more resourcereservations of the candidate resource set, that is associated with afeedback channel corresponding to a received power that is greater thana threshold.
 13. The method of claim 8, wherein the determining thethird resource is further based on at least one of: a received signalreceived power (RSRP), associated with the receiving the controlinformation, being greater than a threshold; or the received power ofthe one or more feedback channel resources being greater than thethreshold.
 14. The method of claim 8, further comprising: receiving anindication of a priority associated with the second resource, whereinthe determining the third resource is further based on at least one of:the priority associated with the second resource; or a priorityassociated with the message.
 15. A method comprising: receiving, by afirst wireless device, at least one configuration parameter forselection of one or more resources to communicate with a second wirelessdevice, wherein the at least one configuration parameter indicates asensing time period for sensing transmission from a third wirelessdevice; determining a first resource from a candidate resource set,wherein the first resource is determined based on: control informationreceived via a second resource occurring in the sensing time period,wherein the control information indicates one or more resourcereservations of the candidate resource set; and a measurement of one ormore feedback channel resources associated with the second resource; andtransmitting, by the first wireless device via the first resource, amessage to the second wireless device.
 16. The method of claim 15,further comprising determining the measurement of the one or morefeedback channel resources associated with the second resource bymeasuring a received power of one or more physical sidelink feedbackchannel (PSFCH) resources associated with the the second resource. 17.The method of claim 15, wherein the determining the first resourcecomprises selecting the first resource from the candidate resource setsuch that one or more reserved resources of the candidate resource setare excluded from selection as the first resource.
 18. The method ofclaim 15, further comprising receiving the control information, whereinthe control information indicates one or more resource reservations ofthe candidate resource set, and wherein the determining the firstresource comprises excluding each resource, of the candidate resourceset, that is associated with a feedback channel corresponding to areceived power that is greater than a threshold.
 19. The method of claim15, wherein the determining the first resource is further based on atleast one of: a received signal received power (RSRP), associated withthe receiving the control information, being greater than a threshold;or the received power of the one or more feedback channel resourcesbeing greater than the threshold.
 20. The method of claim 15, furthercomprising: receiving an indication of a priority associated with thesecond resource, wherein the determining the first resource is furtherbased on at least one of: the priority associated with the secondresource; or a priority associated with the message.